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

165605 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 1517, results 37901 - 37925

Show results on a map

Publication Extents

Not all publications have extents, not all extents are completely accurate
Borates
R.D. Crangle Jr.
2012, Mining Engineering (64) 39-40
Four minerals represent 90 percent of the borates used by industry worldwide — the sodium borates, tincal and kernite; the calcium borate, colemanite; and the sodium-calcium borate, ulexite....
Modeling species invasions in Ecopath with Ecosim: an evaluation using Laurentian Great Lakes models
Brian J. Langseth, Mark Rogers, Hongyan Zhang
2012, Ecological Modelling (247) 251-261
Invasive species affect the structure and processes of ecosystems they invade. Invasive species have been particularly relevant to the Laurentian Great Lakes, where they have played a part in both historical and recent changes to Great Lakes food webs and the fisheries supported therein. There is increased interest in understanding...
A half-million-year record of paleoclimate from the Lake Manix Core, Mojave Desert, California
Marith C. Reheis, Jordon Bright, Steve P. Lund, David M. Miller, Gary Skipp, Robert J. Fleck
2012, Palaeogeography, Palaeoclimatology, Palaeoecology (365-366) 11-37
Pluvial lakes in the southwestern U.S. responded sensitively to past climate through effects on rainfall, runoff, and evaporation. Although most studies agree that pluvial lakes in the southwestern U.S. reached their highest levels coeval with glacial stages, the specific timing of increased effective moisture and lake-level rise is debated, particularly...
Impact disruption and recovery of the deep subsurface biosphere
Charles S. Cockell, Mary A. Voytek, Aaron L. Gronstal, Kai Finster, Julie D. Kirshtein, Kieren Howard, Joachim Reitner, Gregory S. Gohn, Ward E. Sanford, J. Wright Horton Jr., Jens Kallmeyer, Laura Kelly, David S. Powars
2012, Astrobiology (12) 231-246
Although a large fraction of the world's biomass resides in the subsurface, there has been no study of the effects of catastrophic disturbance on the deep biosphere and the rate of its subsequent recovery. We carried out an investigation of the microbiology of a 1.76 km drill core obtained from the...
Evolution of the chemistry of Fe bearing waters during CO2 degassing
J.N. Geroni, C.A. Cravotta III, D.J. Sapsford
2012, Applied Geochemistry (27) 2335-2347
The rates of Fe(II) oxidation and precipitation from groundwater are highly pH dependent. Elevated levels of dissolved CO2 can depress pH and cause difficulty in removing dissolved Fe and associated metals during treatment of ferruginous water. This paper demonstrates interdependent changes in pH, dissolved inorganic C species, and Fe(II) oxidation...
Food security in a changing climate
Roger Pulwarty, Gary Eilerts, James Verdin
2012, Solutions Journal (3) 31-34
By 2080 the effects of climate change—on heat waves, floods, sea level rise, and drought—could push an additional 600 million people into malnutrition and increase the number of people facing water scarcity by 1.8 billion. The precise impacts will, however, strongly depend on socioeconomic conditions such as local markets and...
Heat flow in vapor dominated areas of the Yellowstone Plateau volcanic field: implications for the thermal budget of the Yellowstone Caldera
Shaul Hurwitz, Robert Harris, Cynthia Anne Werner, Fred Murphy
2012, Journal of Geophysical Research B: Solid Earth (117)
Characterizing the vigor of magmatic activity in Yellowstone requires knowledge of the mechanisms and rates of heat transport between magma and the ground surface. We present results from a heat flow study in two vapor dominated, acid-sulfate thermal areas in the Yellowstone Caldera, the 0.11 km2 Obsidian Pool Thermal Area...
Luna B. Leopold--pioneer setting the stage for modern hydrology
Randall J. Hunt, Curt Meine
2012, Ground Water (50) 966-970
In 1986, during the first year of graduate school, the lead author was sampling the water from a pitcher pump in front of “The Shack,” the setting of the opening essays in Aldo Leopold's renowned book A Sand County Almanac. The sampling was part of my Master's work that included...
Mineral resource of the month: rhenium
Desiree E. Polyak
2012, Earth (57) 25-25
Rhenium, a silvery-white, heat resistant metal, has increased significantly in importance since its discovery in 1925. First isolated by a team of German chemists studying platinum ore, the mineral was named for the Rhine River. From 1925 until the 1960s, only two metric tons of rhenium were produced worldwide. Since...
Conflicts between sandhill cranes and farmers in the western United States: evolving issues and solutions
Jane E. Austin
2012, Conference Paper, Cranes, Agriculture and Climate Change, May 28 - June 3, 2010, Muraviovka Park for Sustainable Land Use, Amur Region, Russia
The main conflicts between Sandhill Cranes (Grus canadensis) and farmers in western United States occur in the Rocky Mountain region during migration and wintering periods. Most crop damage by cranes occurs in mature wheat (Triticum aestivum) and barley (Hordeum vulgare), young shoots of alfalfa (Medicago sativa) and cereal grains, chilies...
Habitat use by fishes of Lake Superior. II. Consequences of diel habitat use for habitat linkages and habitat coupling in nearshore and offshore waters
Owen T. Gorman, Daniel L. Yule, Jason D. Stockwell
2012, Aquatic Ecosystem Health & Management (15) 355-368
Diel migration patterns of fishes in nearshore (15–80 m depth) and offshore (>80 m) waters of Lake Superior were examined to assess the potential for diel migration to link benthic and pelagic, and nearshore and offshore habitats. In our companion article, we described three types of diel migration: diel vertical migration (DVM),...
Fragilariopsis diatom evolution in Pliocene and Pleistocene Antarctic shelf sediments
Charlotte Sjunneskog, Christina Riesselman, Diane Winter, Reed Scherer
2012, Micropaleontology (58) 273-289
The late Pliocene – early Pleistocene sediment record in the AND-1B core from the McMurdo Sound, Ross Sea, Antarctica, displays a rich diversity and high abundance of diatoms, including several new morphologies within the genus Fragilariopsis. These new morphologies exhibit similarities to the extinct late Miocene/early Pliocene species Fragilariopsis aurica...
Low genetic diversity and minimal population substructure in the endangered Florida manatee: implications for conservation
Kimberly Pause Tucker, Margaret E. Hunter, Robert K. Bonde, James D. Austin, Ann Marie Clark, Cathy A. Beck, Peter M. McGuire, Madan K. Oli
2012, Journal of Mammalogy (93) 1504-1511
Species of management concern that have been affected by human activities typically are characterized by low genetic diversity, which can adversely affect their ability to adapt to environmental changes. We used 18 microsatellite markers to genotype 362 Florida manatees (Trichechus manatus latirostris), and investigated genetic diversity, population structure, and estimated...
A graphical method to evaluate predominant geochemical processes occurring in groundwater systems for radiocarbon dating
Liang-Feng Han, Niel Plummer, Pradeep Aggarwal
2012, Chemical Geology (318-319) 88-112
A graphical method is described for identifying geochemical reactions needed in the interpretation of radiocarbon age in groundwater systems. Graphs are constructed by plotting the measured 14C, δ13C, and concentration of dissolved inorganic carbon and are interpreted according to specific criteria to recognize water samples that are consistent with a...
From Caprio's lilacs to the USA National Phenology Network
Mark D. Schwartz, Julio L. Betancourt, Jake F. Weltzin
2012, Frontiers in Ecology and the Environment (10) 324-327
Continental-scale monitoring is vital for understanding and adapting to temporal changes in seasonal climate and associated phenological responses. The success of monitoring programs will depend on recruiting, retaining, and managing members of the public to routinely collect phenological observations according to standardized protocols. Here, we trace the development of infrastructure...
Crustal seismicity and the earthquake catalog maximum moment magnitudes (Mcmax) in stable continental regions (SCRs): Correlation with the seismic velocity of the lithosphere
Walter D. Mooney, Jeroen Ritsema, Yong Keun Hwang
2012, Earth and Planetary Science Letters (357-358) 78-83
A joint analysis of global seismicity and seismic tomography indicates that the seismic potential of continental intraplate regions is correlated with the seismic properties of the lithosphere. Archean and Early Proterozoic cratons with cold, stable continental lithospheric roots have fewer crustal earthquakes and a lower maximum earthquake catalog moment magnitude...
Effects of supplemental feeding and aggregation on fecal glucocorticoid metabolite concentrations in elk
Victoria E. Forristal, Scott Creel, Mark L. Taper, Brandon M. Scurlock, Paul C. Cross
2012, Journal of Wildlife Management (76) 76-4
Habitat modifications and supplemental feeding artificially aggregate some wildlife populations, with potential impacts upon contact and parasite transmission rates. Less well recognized, however, is how increased aggregation may affect wildlife physiology. Crowding has been shown to induce stress responses, and increased glucocorticoid (GC) concentrations can reduce immune function and increase...
Highly efficient amplification of chronic wasting disease agent by protein misfolding cyclical amplification with beads (PMCAb)
Chad J. Johnson, Judd M. Aiken, Debbie McKenzie, Michael D. Samuel, Joel A. Pedersen
2012, PLoS ONE (7)
Protein misfolding cyclic amplification (PMCA) has emerged as an important technique for detecting low levels of pathogenic prion protein in biological samples. The method exploits the ability of the pathogenic prion protein to convert the normal prion protein to a proteinase K-resistant conformation. Inclusion of Teflon® beads in the PMCA...
Identifying grasslands suitable for cellulosic feedstock crops in the Greater Platte River Basin: dynamic modeling of ecosystem performance with 250 m eMODIS
Yingxin Gu, Stephen P. Boyte, Bruce K. Wylie, Larry L. Tieszen
2012, GCB Bioenergy (4) 96-106
This study dynamically monitors ecosystem performance (EP) to identify grasslands potentially suitable for cellulosic feedstock crops (e.g., switchgrass) within the Greater Platte River Basin (GPRB). We computed grassland site potential and EP anomalies using 9-year (2000–2008) time series of 250 m expedited moderate resolution imaging spectroradiometer Normalized Difference Vegetation Index...
Hydrogeomorphology of the hyporheic zone: stream solute and fine particle interactions with a dynamic streambed
J. W. Harvey, J.D. Drummond, R.L. Martin, L.E. McPhillips, A.I. Packman, D.J. Jerolmack, S.H. Stonedahl, A.F. Aubeneau, A.H. Sawyer, L. G. Larsen, C.R. Tobias
2012, Journal of Geophysical Research: Biogeosciences (117)
Hyporheic flow in streams has typically been studied separately from geomorphic processes. We investigated interactions between bed mobility and dynamic hyporheic storage of solutes and fine particles in a sand-bed stream before, during, and after a flood. A conservatively transported solute tracer (bromide) and a fine particles tracer (5 μm...
Interdisciplinary research produces results in understanding planetary dunes
Timothy N. Titus, Rosalyn K. Hayward, Cynthia L. Dinwiddie
2012, Eos, Transactions, American Geophysical Union (93) 367-367
Third International Planetary Dunes Workshop: Remote Sensing and Image Analysis of Planetary Dunes; Flagstaff, Arizona, 12–16 June 2012. This workshop, the third in a biennial series, was convened as a means of bringing together terrestrial and planetary researchers from diverse backgrounds with the goal of fostering collaborative interdisciplinary research. The...
Bathythermal habitat use by strains of Great Lakes- and Finger Lakes-origin lake trout in Lake Huron after a change in prey fish abundance and composition
Roger A. Bergstedt, Ray L. Argyle, Charles C. Krueger, William W. Taylor
2012, Transactions of the American Fisheries Society (141) 263-274
A study conducted in Lake Huron during October 1998–June 2001 found that strains of Great Lakes-origin (GLO) lake trout Salvelinus namaycush occupied significantly higher temperatures than did Finger Lakes-origin (FLO; New York) lake trout based on data from archival (or data storage) telemetry tags that recorded only temperature. During 2002...
Fundamental questions of earthquake statistics, source behavior, and the estimation of earthquake probabilities from possible foreshocks
Andrew J. Michael
2012, Bulletin of the Seismological Society of America (102) 2547-2562
Estimates of the probability that an ML 4.8 earthquake, which occurred near the southern end of the San Andreas fault on 24 March 2009, would be followed by an M 7 mainshock over the following three days vary from 0.0009 using a Gutenberg–Richter model of aftershock statistics (Reasenberg and Jones,...
Earthquake ground motion
Nicolas Luco, Michael Valley, C.B. Crouse
2012, Book chapter, 2009 NEHRP Recommended Seismic Provisions: Design Examples (FEMA P-751)
Most of the effort in seismic design of buildings and other structures is focused on structural design. This chapter addresses another key aspect of the design process—characterization of earthquake ground motion. Section 3.1 describes the basis of the earthquake ground motion maps in the Provisions and in ASCE 7. Section...