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

165597 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 1563, results 39051 - 39075

Show results on a map

Publication Extents

Not all publications have extents, not all extents are completely accurate
Nile Delta vegetation response to Holocene climate variability
Christopher E. Bernhardt, Benjamin P. Horton, Jean-Daniel Stanley
2012, Geology (40) 615-618
A 7000 yr palynologic record from Burullus Lagoon, Nile Delta, Egypt, is assessed to investigate changes in terrestrial vegetation in response to Nile flow. Previous studies in this region have shown that sea-level rise in the early to mid-Holocene, and markedly increased human land use during the past several centuries,...
Changes in avian and plant communities of aspen woodlands over 12 years after livestock removal in the northwestern Great Basin
Susan L. Earnst, David S. Dobkin, Jennifer A. Ballard
2012, Conservation Biology (26) 862-872
Riparian and quaking aspen (Populus tremuloides) woodlands are centers of avian abundance and diversity in the western United States, but they have been affected adversely by land use practices, particularly livestock grazing. In 1990, cattle were removed from a 112,500-ha national wildlife refuge in southeastern Oregon. Thereafter, we monitored changes...
Monitoring that matters
Douglas H. Johnson
Robert A. Gitzen, Joshua J. Millspaugh, Andrew B. Cooper, Daniel S. Licht, editor(s)
2012, Book chapter, Design and analysis of long-term ecological monitoring studies
Monitoring is a critically important activity for assessing the status of a system, such as the health of an individual, the balance in one's checking account, profits and losses of a business, the economic activity of a nation, or the size of an animal population. Monitoring is especially vital for...
Benthic community structure and composition in sediment from the northern Gulf of Mexico shoreline, Texas to Florida
Amanda W.J. Demopoulos, Douglas G. Strom
2012, Open-File Report 2012-1153
From April 20 through July 15, 2010, approximately 4.93 million barrels of crude oil spilled into the Gulf of Mexico from the British Petroleum Macondo-1 well, representing the largest spill in U.S. waters. Baseline benthic community conditions were assessed from shoreline sediment samples collected from 56 stations within the swash...
Groundwater-quality data in the Borrego Valley, Central Desert, and Low-Use Basins of the Mojave and Sonoran Deserts study unit, 2008-2010--Results from the California GAMA Program
Timothy M. Mathany, Michael T. Wright, Brandon S. Beuttel, Kenneth Belitz
2012, Data Series 659
Groundwater quality in the 12,103-square-mile Borrego Valley, Central Desert, and Low-Use Basins of the Mojave and Sonoran Deserts (CLUB) study unit was investigated by the U.S. Geological Survey (USGS) from December 2008 to March 2010, as part of the California State Water Resources Control Board (SWRCB) Groundwater Ambient Monitoring and...
Shifting species interactions in terrestrial dryland ecosystems under altered water availability and climate change
Kevin E. McCluney, Jayne Belnap, Scott L. Collins, Angelica L. Gonzalez, Elizabeth M. Hagen, J. Nathaniel Holland, Burt P. Kotler, Fernando T. Maestre, Stanley D. Smith, Blair O. Wolf
2012, Biological Reviews (87) 563-582
Species interactions play key roles in linking the responses of populations, communities, and ecosystems to environmental change. For instance, species interactions are an important determinant of the complexity of changes in trophic biomass with variation in resources. Water resources are a major driver of terrestrial ecology and climate change is...
In situ determination of flocculated suspended material settling velocities and characteristics using a floc camera
David H. Schoellhamer, Dan Haught, Andrew Manning
2012, Conference Paper
Estimates of suspended sediment settling are necessary for numerical sediment models, water quality studies, and rehabilitation of coastal ecosystems. Settling of cohesive sediment, which is common in estuaries, is more difficult to quantify than noncohesive sediment because of flocculation. Flocs are composed of an aggregation of finer silts, clays, and...
Sinks for nitrogen inputs in terrestrial ecosystems: a meta-analysis of 15N tracer field studies
P.H. Templer, M.C. Mack, F. S. Chapin III, L.M. Christenson, J.E. Compton, H.D. Crook, W.S. Currie, C.J. Curtis, D.B. Dail, C. M. D’Antonio, B.A. Emmett, H.E. Epstein, C.L. Goodale, P. Gundersen, S.E. Hobbie, K. Holland, D.U. Hooper, B.A. Hungate, S. Lamontagne, K.J. Nadelhoffer, C.W. Osenberg, S.S. Perakis, P. Schleppi, J. Schimel, I.K. Schmidt, M. Sommerkorn, J. Spoelstra, A. Tietema, W.W. Wessel, D.R. Zak
2012, Ecology (93) 1816-1829
Effects of anthropogenic nitrogen (N) deposition and the ability of terrestrial ecosystems to store carbon (C) depend in part on the amount of N retained in the system and its partitioning among plant and soil pools. We conducted a meta-analysis of studies at 48 sites across four continents that used...
Assessment of potential additions to conventional oil and gas resources in discovered fields of the United States from reserve growth, 2012
U.S. Geological Survey Reserve Growth Assessment Team
2012, Fact Sheet 2012-3108
The U.S. Geological Survey estimated volumes of technically recoverable, conventional petroleum resources that have the potential to be added to reserves from reserve growth in 70 discovered oil and gas accumulations of the United States, excluding Federal offshore areas. The mean estimated volumes are 32 billion barrels of crude oil,...
Bioclimatic predictors for supporting ecological applications in the conterminous United States
Michael S. O’Donnel, Drew A. Ignizio
2012, Data Series 691
The U.S. Geological Survey (USGS) has developed climate indices, referred to as bioclimatic predictors, which highlight climate conditions best related to species physiology. A set of 20 bioclimatic predictors were developed as Geographic Information Systems (GIS) continuous raster surfaces for each year between 1895 and 2009. The Parameter-elevation Regression on...
Mercury bioaccumulation studies in the National Water-Quality Assessment Program--biological data from New York and South Carolina, 2005-2009
Karen M. Beaulieu, Daniel T. Button, Barbara C. Scudder Eikenberry, Karen Riva-Murray, Lia C. Chasar, Paul M. Bradley, Douglas A. Burns
2012, Data Series 705
The U.S. Geological Survey National Water-Quality Assessment Program conducted a multidisciplinary study from 2005–09 to investigate the bioaccumulation of mercury in streams from two contrasting environmental settings. Study areas were located in the central Adirondack Mountains region of New York and the Inner Coastal Plain of South Carolina. Fish, macroinvertebrates,...
Locations and attributes of utility-scale solar power facilities in Colorado and New Mexico, 2011
Drew A. Ignizio, Natasha B. Carr
2012, Data Series 693
The data series consists of polygonal boundaries for utility-scale solar power facilities (both photovoltaic and concentrating solar power) located within Colorado and New Mexico as of December 2011. Attributes captured for each facility include the following: facility name, size/production capacity (in MW), type of solar technology employed, location, state, operational...
Probabilistic prediction of barrier-island response to hurricanes
Nathaniel G. Plant, Hilary F. Stockdon
2012, Journal of Geophysical Research (117)
Prediction of barrier-island response to hurricane attack is important for assessing the vulnerability of communities, infrastructure, habitat, and recreational assets to the impacts of storm surge, waves, and erosion. We have demonstrated that a conceptual model intended to make qualitative predictions of the type of beach response to storms (e.g.,...
Effects of brush management on the hydrologic budget and water quality in and adjacent to Honey Creek State Natural Area, Comal County, Texas, 2001--10
J. Ryan Banta, Richard N. Slattery
2012, Fact Sheet 2012-3097
Woody vegetation, including ashe juniper (Juniperus ashei), has encroached on some areas in central Texas that were historically oak grassland savannah. Encroachment of woody vegetation is generally attributed to overgrazing and fire suppression. Removing the ashe juniper and allowing native grasses to reestablish in the area as a brush management...
Geologic map of the Alley Spring quadrangle, Shannon County, Missouri
David J. Weary, Randall C. Orndorff
2012, Scientific Investigations Map 3161
The Alley Spring 7.5-minute quadrangle is located in south-central Missouri within the Salem Plateau region of the Ozark Plateaus physiographic province. About 1,990 feet (ft) of flat-lying to gently dipping Lower Paleozoic sedimentary rocks, mostly dolomite, chert, sandstone, and orthoquartzite, overlie Mesoproterozoic volcanic rocks. A small exposure of the volcanic...
Estimating tag loss of the Atlantic Horseshoe crab, Limulus polyphemus, using a multi-state model
Catherine Alyssa Butler, Conor P. McGowan, J. Barry Grand, David Smith
2012, Conference Paper
The Atlantic Horseshoe crab, Limulus polyphemus, is a valuable resource along the Mid-Atlantic coast which has, in recent years, experienced new management paradigms due to increased concern about this species role in the environment. While current management actions are underway, many acknowledge the need for improved and updated parameter estimates...
Forecasting climate change impacts to plant community composition in the Sonoran Desert region
Seth M. Munson, Robert H. Webb, Jayne Belnap, J. Andrew Hubbard, Don E. Swann, Sue Rutman
2012, Global Change Biology (18) 1083-1095
Hotter and drier conditions projected for the southwestern United States can have a large impact on the abundance and composition of long-lived desert plant species. We used long-term vegetation monitoring results from 39 large plots across four protected sites in the Sonoran Desert region to determine how plant species have...
Geospatial datasets for watershed delineation and characterization used in the Hawaii StreamStats web application
Alan Rea, Kenneth D. Skinner
2012, Data Series 680
The U.S. Geological Survey Hawaii StreamStats application uses an integrated suite of raster and vector geospatial datasets to delineate and characterize watersheds. The geospatial datasets used to delineate and characterize watersheds on the StreamStats website, and the methods used to develop the datasets are described in this report. The datasets...
Introduction to the 8th International Workshop on Smoltification and a synthesis of major findings
Carl B. Schreck, Steven D. McCormick, Björn Thrandur Björnsson, Sigurd O. Stefansson, Hiroshi Ueda
2012, Aquaculture (362-363) 98-100
The early life history of anadromous salmonid fishes, be they Atlantic (Salmo salar) or Pacific salmon (Oncorhynchus spp.), trout of those genera, or charrs (Salvelinus spp.), appears much more complex than previously thought. The seaward movement or migration is extremely polymorphic among and within species. To help provide understanding of...
Sediment loads in the Red River of the North and selected tributaries near Fargo, North Dakota, 2010--2011
Joel M. Galloway, Rochelle A. Nustad
2012, Scientific Investigations Report 2012-5111
Natural-resource agencies are concerned about possible geomorphic effects of a proposed diversion project to reduce the flood risk in the Fargo-Moorhead metropolitan area. The U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers collected data in the spring of 2010 and 2011, and from June to November...
Practical estimates of field-saturated hydraulic conductivity of bedrock outcrops using a modified bottomless bucket method
Benjamin B. Mirus, Kim S. Perkins
2012, Water Resources Research (48)
The bottomless bucket (BB) approach (Nimmo et al., 2009a) is a cost-effective method for rapidly characterizing field-saturated hydraulic conductivity Kfs of soils and alluvial deposits. This practical approach is of particular value for quantifying infiltration rates in remote areas with limited accessibility. A similar approach for bedrock outcrops is also...
USGS Zebra Mussel Monitoring Program for north Texas
Christopher J. Churchill, Stanley Baldys
2012, Fact Sheet 2012-3077
The U.S. Geological Survey (USGS) Zebra Mussel Monitoring Program for north Texas provides early detection and monitoring of zebra mussels (Dreissena polymorpha) by using a holistic suite of detection methods. The program is designed to assess zebra mussel occurrence, distribution, and densities in north Texas waters by using four approaches:...
Dawn at Vesta: testing the protoplanetary paradigm
C.T. Russell, C.A. Raymond, A. Coradini, H.Y. McSween, M.T. Zuber, A. Nathues, Maria-Cristina DeSanctis, R. Jaumann, A.S. Konopliv, F. Preusker, S.W. Asmar, R.S. Park, R. Gaskell, H.U. Keller, S. Mottola, T. Roatsch, J.E.C. Scully, D.E. Smith, P. Tricarico, M.J. Toplis, U.R. Christensen, W. C. Feldman, D. J. Lawrence, T.J. McCoy, T.H. Prettyman, R.C. Reedy, M.E. Sykes, T.N. Titus
2012, Science (336) 684-686
The Dawn spacecraft targeted 4 Vesta, believed to be a remnant intact protoplanet from the earliest epoch of solar system formation, based on analyses of howardite-eucrite-diogenite (HED) meteorites that indicate a differentiated parent body. Dawn observations reveal a giant basin at Vesta's south pole, whose excavation was sufficient to produce...
Volatile organic compounds in the unsaturated zone from radioactive wastes
Ronald J. Baker, Brian J. Andraski, David A. Stonestrom, Wentai Luo
2012, Journal of Environmental Quality (41) 1324-1336
Volatile organic compounds (VOCs) are often comingled with low-level radioactive wastes (LLRW), but little is known about subsurface VOC emanations from LLRW landfills. The current study systematically quantified VOCs associated with LLRW over an 11-yr period at the USGS Amargosa Desert Research Site (ADRS) in southwestern Nevada. Unsaturated-zone gas samples...