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Page 562, results 14026 - 14050

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Sea otters are recolonizing southern California in fits and starts
Kevin D. Lafferty, M. Tim Tinker
2014, Ecosphere (5)
After near extinction as a result of the fur trade in the 1700s and 1800s, the southern sea otter slowly reoccupied the core of its range in central California. Range expansion beyond central California is seen as key to full recovery of otters, but the rate of expansion has been...
Water levels and water quality in the Sparta-Memphis aquifer (middle Claiborne aquifer) in Arkansas, spring-summer 2011
T. P. Schrader
2014, Scientific Investigations Report 2014-5044
The U.S. Geological Survey, in cooperation with the Arkansas Natural Resources Commission and the Arkansas Geological Survey, has monitored water levels in the Sparta Sand of Claiborne Group and Memphis Sand of Claiborne Group (herein referred to as “the Sparta Sand” and “the Memphis Sand,” respectively) since the 1920s. Groundwater...
Physiological and ecological effects of increasing temperature on fish production in lakes of Arctic Alaska
Michael P. Carey, Christian E. Zimmerman
2014, Ecology and Evolution (4) 1981-1993
Lake ecosystems in the Arctic are changing rapidly due to climate warming. Lakes are sensitive integrators of climate-induced changes and prominent features across the Arctic landscape, especially in lowland permafrost regions such as the Arctic Coastal Plain of Alaska. Despite many studies on the implications of climate warming, how fish...
Porphyry copper assessment of eastern Australia
Arthur A. Bookstrom, Richard A. Len, Jane M. Hammarstrom, Gilpin R. Robinson Jr., Michael L. Zientek, Benjamin J. Drenth, Subhash Jaireth, Pamela M. Cossette, John C. Wallis
2014, Scientific Investigations Report 2010-5090-L
The U.S. Geological Survey (USGS) conducts national and global assessments of resources (mineral, energy, water, and biologic) to provide science in support of decision making. Mineral resource assessments provide syntheses of available information about where mineral deposits are known and suspected to occur in the Earth’s crust and which commodities...
Hydrological controls on methylmercury distribution and flux in a tidal marsh
Hua Zhang, Kevan B. Moffett, Lisamarie Windham-Myers, Steven M. Gorelick
2014, Environmental Science & Technology (48) 6795-6804
The San Francisco Estuary, California, contains mercury (Hg) contamination originating from historical regional gold and Hg mining operations. We measured hydrological and geochemical variables in a tidal marsh of the Palo Alto Baylands Nature Preserve to determine the sources, location, and magnitude of hydrological fluxes of methylmercury (MeHg), a bioavailable...
Status and understanding of groundwater quality in the South Coast Interior groundwater basins, 2008: California GAMA Priority Basin Project
Mary C. Parsons, Justin T. Kulongoski, Kenneth Belitz
2014, Scientific Investigations Report 2014-5023
Groundwater quality in the approximately 653-square-mile (1,691-square-kilometer) South Coast Interior Basins (SCI) study unit was investigated as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The South Coast Interior Basins study unit contains eight priority groundwater basins grouped into three study areas, Livermore,...
Groundwater quality in the South Coast Interior Basins, California
Mary C. Parsons, Kenneth Belitz
2014, Fact Sheet 2013-3088
Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s untreated groundwater quality and increases public access...
Adaptive nest clustering and density-dependent nest survival in dabbling ducks
Kevin M. Ringelman, John M. Eadie, Joshua T. Ackerman
2014, Oikos (123) 239-247
Density-dependent population regulation is observed in many taxa, and understanding the mechanisms that generate density dependence is especially important for the conservation of heavily-managed species. In one such system, North American waterfowl, density dependence is often observed at continental scales, and nest predation has long been implicated as a key...
Two graphical user interfaces for managing and analyzing MODFLOW groundwater-model scenarios
Edward R. Banta
2014, Techniques and Methods 6-A50
Scenario Manager and Scenario Analyzer are graphical user interfaces that facilitate the use of calibrated, MODFLOW-based groundwater models for investigating possible responses to proposed stresses on a groundwater system. Scenario Manager allows a user, starting with a calibrated model, to design and run model scenarios by adding or modifying stresses...
Origins and delineation of saltwater intrusion in the Biscayne aquifer and changes in the distribution of saltwater in Miami-Dade County, Florida
Scott T. Prinos, Michael A. Wacker, Kevin J. Cunningham, David V. Fitterman
2014, Scientific Investigations Report 2014-5025
Intrusion of saltwater into parts of the shallow karst Biscayne aquifer is a major concern for the 2.5 million residents of Miami-Dade County that rely on this aquifer as their primary drinking water supply. Saltwater intrusion of this aquifer began when the Everglades were drained to provide dry land for...
Evaluation of sensor types and environmental controls on mapping biomass of coastal marsh emergent vegetation
Kristin B. Byrd, Jessica L. O'Connell, Stefania Di Tommaso, Maggi Kelly
2014, Remote Sensing of Environment (149) 166-180
There is a need to quantify large-scale plant productivity in coastal marshes to understand marsh resilience to sea level rise, to help define eligibility for carbon offset credits, and to monitor impacts from land use, eutrophication and contamination. Remote monitoring of aboveground biomass of emergent wetland vegetation will help address...
Land use patterns, ecoregion, and microcystin relationships in U.S. lakes and reservoirs: a preliminary evaluation
John R. Beaver, Erin E. Manis, Keith A. Loftin, Jennifer L. Graham, Amina I. Pollard, Richard M. Mitchell
2014, Harmful Algae (36) 57-62
A statistically significant association was found between the concentration of total microcystin, a common class of cyanotoxins, in surface waters of lakes and reservoirs in the continental U.S. with watershed land use using data from 1156 water bodies sampled between May and October 2007 as part of the USEPA National...
Avian influenza virus antibodies in Pacific Coast Red Knots (Calidris canutus rufa)
James A. Johnson, Lucas H. DeCicco, Daniel R. Ruthrauff, Scott Krauss, Jeffrey S. Hall
2014, Journal of Wildlife Diseases (50) 671-675
Prevalence of avian influenza virus (AIV) antibodies in the western Atlantic subspecies of Red Knot (Calidris canutus rufa) is among the highest for any shorebird. To assess whether the frequency of detection of AIV antibodies is high for the species in general or restricted only to C. c. rufa, we...
Comparative biogeochemistry-ecosystem-human interactions on dynamic continental margins
Lisa A. Levin, Kon-Kee Liu, Kay-Christian Emeis, Denise L. Breitburg, James Cloern, Curtis Deutsch, Michele Giani, Anne Goffart, Eileen E. Hofmann, Zouhair Lachkar, Karin Limburg, Su-Mei Liu, Enrique Montes, Wajih Naqvi, Olivier Ragueneau, Christophe Rabouille, Santosh Kumar Sarkar, Dennis P. Swaney, Paul Wassman, Karen F. Wishner
2014, Journal of Marine Systems (141) 3-17
The ocean’s continental margins face strong and rapid change, forced by a combination of direct human activity, anthropogenic CO2-induced climate change, and natural variability. Stimulated by discussions in Goa, India at the IMBER IMBIZO III, we (1) provide an overview of the drivers of biogeochemical variation and change on margins,...
Phytoplankton primary production in the world's estuarine-coastal ecosystems
James E. Cloern, S.Q. Foster, A.E. Kleckner
2014, Biogeosciences (11) 2477-2501
Estuaries are biogeochemical hot spots because they receive large inputs of nutrients and organic carbon from land and oceans to support high rates of metabolism and primary production. We synthesize published rates of annual phytoplankton primary production (APPP) in marine ecosystems influenced by connectivity to land – estuaries, bays, lagoons,...
Tracking change over time: River flooding
Water Resources Division, U.S. Geological Survey
2014, General Information Product 133-A
Landsat satellites have been capturing images of Earth from space since 1972. These images provide a long-term record of natural and human-induced changes on the global landscape. Comparing images from multiple years reveals slow and subtle changes as well as rapid and devastating ones. Landsat images are available from the...
Long-term soil monitoring at U.S. Geological Survey reference watersheds
Michael R. McHale, Jason Siemion, Gregory B. Lawrence, M. Alisa Mast
2014, Fact Sheet 2014-3002
Monitoring the environment by making repeated measurements through time is essential to evaluate and track the health of ecosystems (fig. 1). Long-term datasets produced by such monitoring are indispensable for evaluating the effectiveness of environmental legislation and for designing mitigation strategies to address environmental changes in an era when human...
Invasive lionfish use a diversity of habitats in Florida
Pamela J. Schofield, Lad Akins, Denise R. Gregoire-Lucente, Rachel J. Pawlitz
2014, Fact Sheet 2014-3032
Two species of lionfish (Pterois volitans and Pterois miles) are the first marine fishes known to invade and establish self-sustaining populations along the eastern seaboard of the United States. First documented off the coast of Florida in 1985, lionfish are now found along the Atlantic coast of the United States...
Distribution, abundance, and migration timing of Greater and Lesser Sandhill Cranes wintering in the Sacramento-San Joaquin River Delta region of California
Gary L. Ivey, Bruce D. Dugger, Caroline P. Herziger, Michael L. Casazza, Joseph P. Fleskes
2014, Book, Proceedings of the North American Crane Workshop
The Sacramento-San Joaquin River Delta region of California (hereafter, Delta region) is an important wintering region for the Central Valley Population of greater sandhill cranes (Grus canadensis tabida) and lesser sandhill cranes (G. c. canadensis), but basic information about the ecology of these birds is lacking to design a biologically sound conservation strategy....
Investigating the importance of sediment resuspension in Alexandrium fundyense cyst population dynamics in the Gulf of Maine
Bradford Butman, Alfredo L. Aretxabaleta, Patrick J. Dickhudt, P. Soupy Dalyander, Christopher R. Sherwood, Donald M. Anderson, Bruce A. Keafer, Richard P. Signell
2014, Deep-Sea Research Part II: Topical Studies in Oceanography (103) 79-95
Cysts of Alexandrium fundyense, a dinoflagellate that causes toxic algal blooms in the Gulf of Maine, spend the winter as dormant cells in the upper layer of bottom sediment or the bottom nepheloid layer and germinate in spring to initiate new blooms. Erosion measurements were made on sediment cores collected...
Stratigraphic controls on fluid and solute fluxes across the sediment-water interface of an estuary
Audrey H. Sawyer, Olesya Lazareva, Kevin D. Kroeger, Kyle Crespo, Clara S. Chan, Thomas Stieglitz, Holly A. Michael
2014, Limnology and Oceanography (59) 997-1010
Shallow stratigraphic features, such as infilled paleovalleys, modify fresh groundwater discharge to coastal waters and fluxes of saltwater and nutrients across the sediment–water interface. We quantify the spatial distribution of shallow surface water–groundwater exchange and nitrogen fluxes near a paleovalley in Indian River Bay, Delaware, using a hand resistivity probe,...
Mechanisms of aquatic species invasions across the SALCC - an update
Amy J. Benson
2014, Report
The USGS Nonindigenous Aquatic Species Database (NAS; nas.er.usgs.gov) is a comprehensive tool for demonstrating where and when nonindigenous species have been sighted across the U.S. Information in the database is used for state-level invasive species management plans, to focus monitoring efforts, for public education, predictive modeling, and for avoiding unintentional...
Water resources of Orleans Parish, Louisiana
Lawrence B. Prakken, Vincent E. White, John K. Lovelace
2014, Fact Sheet 2014-3017
Information concerning the availability, use, and quality of water in Orleans Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. Information on the availability,...
Water resources of Terrebonne Parish, Louisiana
Lawrence B. Prakken, John K. Lovelace, Vincent E. White
2014, Fact Sheet 2014-3016
Information concerning the availability, use, and quality of water in Terrebonne Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. Information on the availability,...
Nutrient budgets, marsh inundation under sea-level rise scenarios, and sediment chronologies for the Bass Harbor Marsh estuary at Acadia National Park
Thomas G. Huntington, Charles W. Culbertson, Christopher C. Fuller, Patricia Glibert, Luke Sturtevant
2014, Open-File Report 2014-1031
Eutrophication in the Bass Harbor Marsh estuary on Mount Desert Island, Maine, is an ongoing problem manifested by recurring annual blooms of green macroalgae species, principally Enteromorpha prolifera and Enteromorpha flexuosa, blooms that appear in the spring and summer. These blooms are unsightly and impair the otherwise natural beauty of...