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

68892 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 455, results 11351 - 11375

Show results on a map

Publication Extents

Not all publications have extents, not all extents are completely accurate
Captive propagation, reproductive biology, and early life history of Etheostoma wapiti (Boulder Darter), E. vulneratum (Wounded Darter), and E. maculatum (Spotted Darter)
Crystal L. Ruble, Patrick L. Rakes, John R. Shute, Stuart A. Welsh
2016, Southeastern Naturalist (15) 115-126
Reproductive biology and early life-history data are important for understanding the ecology of fishes. In 2008, we conducted captive propagation studies on 3 species of darters of the subgenus Nothonotus: Etheostoma wapiti (Boulder Darter), E. vulneratum (Wounded Darter), and E. maculatum (Spotted Darter). The length of spawning period...
Development and application of freshwater sediment-toxicity benchmarks for currently used pesticides
Lisa H. Nowell, Julia E. Norman, Christopher G. Ingersoll, Patrick W. Moran
2016, Science of the Total Environment (550) 835-850
Sediment-toxicity benchmarks are needed to interpret the biological significance of currently used pesticides detected in whole sediments. Two types of freshwater sediment benchmarks for pesticides were developed using spiked-sediment bioassay (SSB) data from the literature. These benchmarks can be used to interpret sediment-toxicity data or to assess the potential toxicity...
It’s what’s inside that counts: Egg contaminant concentrations are influenced by estimates of egg density, egg volume, and fresh egg mass
Mark P. Herzog, Joshua T. Ackerman, Collin A. Eagles-Smith, C. Alex Hartman
2016, Ecotoxicology (25) 770-776
In egg contaminant studies, it is necessary to calculate egg contaminant concentrations on a fresh wet weight basis and this requires accurate estimates of egg density and egg volume. We show that the inclusion or exclusion of the eggshell can influence egg contaminant concentrations, and we provide estimates of egg...
Determining the 95% limit of detection for waterborne pathogen analyses from primary concentration to qPCR
Joel P. Stokdyk, Aaron D. Firnstahl, Susan K. Spencer, Tucker R Burch, Mark A. Borchardt
2016, Water Research (96) 105-113
The limit of detection (LOD) for qPCR-based analyses is not consistently defined or determined in studies on waterborne pathogens. Moreover, the LODs reported often reflect the qPCR assay alone rather than the entire sample process. Our objective was to develop an approach to determine the 95% LOD (lowest concentration at...
Establishing a pre-mining geochemical baseline at a uranium mine near Grand Canyon National Park, USA
David L. Naftz, Katherine Walton-Day
2016, Geoderma (7) 76-92
During 2012, approximately 404,000 ha of Federal Land in northern Arizona was withdrawn from consideration of mineral extraction for a 20-year period to protect the Grand Canyon watershed from potentially adverse effects of U mineral exploration and development. The development, operation, and reclamation of the Canyon Mine during the withdrawal...
Habitat use and foraging patterns of molting male Long-tailed Ducks in lagoons of the central Beaufort Sea, Alaska
Paul L. Flint, John A. Reed, Deborah Lacroix, Richard Lanctot
2016, Arctic (69) 19-28
From mid-July through September, 10 000 to 30 000 Long-tailed Ducks (Clangula hyemalis) use the lagoon systems of the central Beaufort Sea for remigial molt. Little is known about their foraging behavior and patterns of habitat use during this flightless period. We used radio transmitters to track male Long-tailed Ducks...
Riparian groundwater and baseflow studies in the Upper Colorado River Basin
Lindsay Reynolds, Patrick B. Shafroth
2016, Report, Ruth Powell Hutchins Water Center Scientific and technical report series
Executive summary As part of an ongoing effort to understand baseflow in the Upper Colorado River Basin (UCRB) and implications for stream-dependent ecosystems, we conducted a brief review of literature related to groundwater and baseflow in the UCRB. We included primary literature, federal and state resources, databases and gray literature studies...
Predictive mapping of seabirds, pinnipeds and cetaceans off the Pacific Coast of Washington
Charles Menza, Jeffery B. Leirness, Tim White, Arliss Winship, Brian P. Kinlan, Laura Kracker, Jeannette E. Zamon, Lisa Ballance, Elizabeth Becker, Karin A. Forney, Jay Barlow, Josh Adams, David Pereksta, Scott Pearson, John Pierce, Steven J. Jeffries, John Calambokidis, Annie Douglas, Bradford C. Hanson, Scott R. Benson, Liam Antrim
2016, Report
About this report This report supports Washington-led marine spatial planning and responsible stewardship of natural and cultural resources by the Olympic Coast National Marine Sanctuary. Washington state agencies and the sanctuary continually seek the best available science to improve management of marine uses and stewardship of resources (Etheridge et al., 2010;...
Mercury transformation and release differs with depth and time in a contaminated riparian soil during simulated flooding
Brett Poulin, George R. Aiken, Kathryn L. Nagy, Alain Manceau, David P. Krabbenhoft, Joseph N. Ryan
2016, Geochimica et Cosmochimica Acta (176) 118-138
Riparian soils are an important environment in the transport of mercury in rivers and wetlands, but the biogeochemical factors controlling mercury dynamics under transient redox conditions in these soils are not well understood. Mercury release and transformations in the Oa and underlying A horizons of a contaminated riparian soil were...
Isotope hydrology of the Chalk River Laboratories site, Ontario, Canada
Zell E. Peterman, Leonid A. Neymark, K.J. King-Sharp, Mel Gascoyne
2016, Applied Geochemistry (66) 149-161
This paper presents results of hydrochemical and isotopic analyses of groundwater (fracture water) and porewater, and physical property and water content measurements of bedrock core at the Chalk River Laboratories (CRL) site in Ontario. Density and water contents were determined and water-loss porosity values were calculated for core samples. Average...
Elevation dynamics in a restored versus a submerging salt marsh in Long Island Sound
Shimon C. Anisfeld, Troy D. Hill, Donald R. Cahoon
2016, Estuarine, Coastal and Shelf Science (170) 145-154
Accelerated sea-level rise (SLR) poses the threat of salt marsh submergence, especially in marshes that are relatively low-lying. At the same time, restoration efforts are producing new low-lying marshes, many of which are thriving and avoiding submergence. To understand the causes of these different fates, we studied two Long Island...
Detection of an enigmatic plethodontid Salamander using Environmental DNA
Todd W. Pierson, Anna M. McKee, Stephen F. Spear, John C. Maerz, Carlos D. Camp, Travis C. Glenn
2016, Copeia (104) 78-82
The isolation and identification of environmental DNA (eDNA) offers a non-invasive and efficient method for the detection of rare and secretive aquatic wildlife, and it is being widely integrated into inventory and monitoring efforts. The Patch-Nosed Salamander (Urspelerpes brucei) is a tiny, recently discovered species of plethodontid salamander known only...
Lake Ontario benthic prey fish assessment, 2015
Brian Weidel, Maureen Walsh, Jeremy P. Holden, Michael J. Connerton
2016, NYSDEC Lake Ontario Annual Report 2015-12b
Benthic prey fishes are a critical component of the Lake Ontario food web, serving as energy vectors from benthic invertebrates to native and introduced piscivores. Since the late 1970’s, Lake Ontario benthic prey fish status was primarily assessed using bottom trawl observations confined to the lake’s south shore, in waters...
Walter Rowe Courtenay, Jr. (1933–2014)
Amy J. Benson
2016, Copeia (104) 297-299
WALTER R. COURTENAY, JR., ichthyologist and retired professor, Florida Atlantic University, Boca Raton, Florida, died in Gainesville, Florida, on 30 January 2014 at age 80. Walt was born in Neenah, Wisconsin, on 6 November 1933, son of Walter and Emily Courtenay. Walt's interest in fish began at a young age...
Groundwater conditions in Utah, spring of 2016
Carole B. Burden
2016, Cooperative Investigations Report 57
This is the fifty-third in a series of annual reports that describe groundwater conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality, provide...
Capsule- and disk-filter procedure
Stanley C. Skrobialowski
2016, Techniques of Water-Resources Investigations 9-A5
Capsule and disk filters are disposable, self-contained units composed of a pleated or woven filter medium encased in a polypropylene or other plastic housing that can be connected inline to a sample-delivery system (such as a submersible or peristaltic pump) that generates sufficient pressure (positive or negative) to force water...
Preliminary characterization of nitrogen and phosphorus in groundwater discharging to Lake Spokane, northeastern Washington, using stable nitrogen isotopes
Andrew S. Gendaszek, Stephen E. Cox, Andrew R. Spanjer
2016, Open-File Report 2016-1029
Lake Spokane, locally referred to as Long Lake, is a 24-mile-long section of the Spokane River impounded by Long Lake Dam that has, in recent decades, experienced water-quality problems associated with eutrophication. Consumption of oxygen by the decomposition of aquatic plants that have proliferated because of high nutrient concentrations has...
Dragonfly Mercury Project—A citizen science driven approach to linking surface-water chemistry and landscape characteristics to biosentinels on a national scale
Collin A. Eagles-Smith, Sarah J. Nelson, Willacker Jr., Colleen M. Flanagan Pritz, David P. Krabbenhoft
2016, Fact Sheet 2016-3005
Mercury is a globally distributed pollutant that threatens human and ecosystem health. Even protected areas, such as national parks, are subjected to mercury contamination because it is delivered through atmospheric deposition, often after long-range transport. In aquatic ecosystems, certain environmental conditions can promote microbial processes that convert inorganic mercury to...
Holocene climate variability and anthropogenic impacts from Lago Paixban, a perennial wetland in Peten, Guatemala
David B. Wahl, Richard D. Hansen, Roger Byrne, Lysanna Anderson, T. Schreiner
2016, Global and Planetary Change (138) 70-81
Analyses of an ~ 6 m sediment core from Lago Paixban in Peten, Guatemala, document the complex evolution of a perennial wetland over the last 10,300 years. The basal sediment is comprised of alluvial/colluvial fill deposited in the early Holocene. The absence of pollen and gastropods in the basal sediments...
Physical, chemical, and biological characteristics of selected headwater streams along the Allegheny Front, Blair County, Pennsylvania, July 2011–September 2013
Dennis J. Low, Robin A. Brightbill, Heather L. Eggleston, Jeffrey J. Chaplin
2016, Open-File Report 2015-1173
The Altoona Water Authority (AWA) obtains all of its water supply from headwater streams that drain western Blair County, an area underlain in part by black shale of the Marcellus Formation. Development of the shale-gas reservoirs will require new access roads, stream crossing, drill-pad construction, and pipeline installation, activities that...
Influence of vertical and lateral heat transfer on permafrost thaw, peatland landscape transition, and groundwater flow
Barret L. Kurylyk, Masaki Hayashi, William L. Quinton, Jeffrey M. McKenzie, Clifford I. Voss
2016, Water Resources Research (52) 1286-1305
Recent climate change has reduced the spatial extent and thickness of permafrost in many discontinuous permafrost regions. Rapid permafrost thaw is producing distinct landscape changes in the Taiga Plains of the Northwest Territories, Canada. As permafrost bodies underlying forested peat plateaus shrink, the landscape slowly transitions into unforested wetlands. The...
Statistical analysis and mapping of water levels in the Biscayne aquifer, water conservation areas, and Everglades National Park, Miami-Dade County, Florida, 2000–2009
Scott T. Prinos, Joann F. Dixon
2016, Scientific Investigations Report 2016-5005
Statistical analyses and maps representing mean, high, and low water-level conditions in the surface water and groundwater of Miami-Dade County were made by the U.S. Geological Survey, in cooperation with the Miami-Dade County Department of Regulatory and Economic Resources, to help inform decisions necessary for urban planning and development. Sixteen...
Water use in the Apalachicola-Chattahoochee-Flint River Basin, Alabama, Florida, and Georgia, 2010, and water-use trends, 1985-2010
Stephen J. Lawrence
2016, Scientific Investigations Report 2016-5007
The Apalachicola-Chattahoochee-Flint (ACF) River Basin encompasses about 20,230 square miles in parts of Alabama, Florida, and Georgia. Increasing population growth and agricultural production from the 1970s to 2010 has prompted increases in water-resources development and substantially increased water demand in the basin. Since the 1980s, Alabama, Florida, Georgia, and the...
Groundwater
David A. Stonestrom
Ellen E. Wohl, editor(s)
2016, Book chapter, Oxford Bibliographies in Environmental Science
Introduction Groundwater represents the terrestrial subsurface component of the hydrologic cycle. As such, groundwater is generally in motion, moving from elevated areas of recharge to lower areas of discharge. Groundwater usually moves in accordance with Darcy’s law (Dalmont, Paris: Les Fontaines Publiques de la Ville de Dijon, 1856). Groundwater residence times...
A full annual cycle modeling framework for American black ducks
Orin J. Robinson, Conor P. McGowan, Patrick K. Devers, Rodney W. Brook, Min Huang, Malcom Jones, Daniel G. McAuley, Guthrie S. Zimmerman
2016, Natural Resource Modeling (29) 159-174
American black ducks (Anas rubripes) are a harvested, international migratory waterfowl species in eastern North America. Despite an extended period of restrictive harvest regulations, the black duck population is still below the population goal identified in the North American Waterfowl Management Plan (NAWMP). It has been hypothesized that density-dependent factors...