New land surface digital elevation model covers the Earth
Dean B. Gesch, Kristine L. Verdin, Susan K. Greenlee
1999, Eos, Earth and Space Science News (80) 69-70
Land surface elevation around the world is reaching new heights—as far as its description and measurement goes. A new global digital elevation model (DEM) is being cited as a significant improvement in the quality of topographic data available for Earth science studies.Land surface elevation is one of the Earth's most...
A GIS modeling method applied to predicting forest songbird habitat
Randy Dettmers, Jonathan Bart
1999, Ecological Applications (9) 152-163
We have developed an approach for using “presence” data to construct habitat models. Presence data are those that indicate locations where the target organism is observed to occur, but that cannot be used to define locations where the organism does not occur. Surveys of highly mobile vertebrates often yield these...
Comment on “Field study of spatial variability in unsaturated flow beneath and adjacent to playas” by Bridget R. Scanlon and Richard S. Goldsmith
Warren W. Wood
1999, Water Resources Research (35) 601-601
The Scanlon and Goldsmith [1997] paper contains a wealth of data that provides a useful contribution to the understanding of...
Factors influencing estimation of pesticide-related wildlife mortality
N.B. Vyas
1999, Toxicology and Industrial Health (15) 187-192
Free-ranging wildlife is regularly exposed to pesticides and can serve as a sentinel for human and environmental health. Therefore a comprehensive pesticide hazard assessment must incorporate the effects of actual applications on free-ranging wildlife. Mortality is the most readily reported wildlife effect, and the significance of these...
Characterizing fish community diversity across Virginia landscapes: Prerequisite for conservation
Paul L. Angermeier, M.R. Winston
1999, Ecological Applications (9) 335-349
The number of community types occurring within landscapes is an important, but often unprotected, component of biological diversity. Generally applicable protocols for characterizing community diversity need to be developed to facilitate conservation. We used several multivariate techniques to analyze geographic variation in the composition of fish communities in Virginia streams....
Multiscale thermal refugia and stream habitat associations of chinook salmon in northwestern Oregon
Christian E. Torgersen, David M. Price, Hiram W. Li, B.A. McIntosh
1999, Ecological Applications (9) 301-319
We quantified distribution and behavior of adult spring chinook salmon (Oncorhynchus tshawytscha) related to patterns of stream temperature and physical habitat at channel-unit, reach-, and section-level spatial scales in a wilderness stream and a disturbed stream in the John Day River basin in northeastern Oregon....
Zooplankton variability and larval striped bass foraging: Evaluating potential match/mismatch regulation
John H. Chick, Michael J. Van Den Avyle
1999, Ecological Applications (9) 320-334
We quantified temporal and spatial variability of zooplankton in three potential nursery sites (river, transition zone, lake) for larval striped bass (Morone saxatilis) in Lake Marion, South Carolina, during April and May 1993–1995. In two of three years, microzooplankton (rotifers and copepod nauplii) density was significantly greater in the lake...
Future of gas hydrate research
D.E. Sloan, P.G. Brewer, C. K. Paull, Timothy S. Collett, W. Steven Holbrook, Keith A. Kvenvolden
1999, Eos, Earth and Space Science News (80) 247-248
Methane hydrates are ice‐like inclusion compounds, in which every volume of hydrate can contain as much as 180 volumes (STP) of gas.The amount of methane in natural gas hydrates is twice the total recoverable fossil fuel reserve. Because of their natural abundance in oceans and permafrost, hydrates have become an...
Creation of a 30-meter land cover database for the conterminous United States—Accomplishments and future goals
Terry L. Sohl, James Vogelmann, B.K. Wylie, Charles R. Larson, J. Nicholas Van Driel
1999, Conference Paper
Double-disk solid-phase extraction--Simultaneous cleanup and trace enrichment of herbicides and metabolites from environmental samples
Imma Ferrar, Damia Barcelo, E.M. Thurman
1999, Analytical Chemistry (71) 1009-1015
Phenylurea and triazine herbicides, including some metabolites, were isolated from water and soil extracts by solid-phase extraction using a layered system of two extraction disks, a method called double-disk solid-phase extraction. The first disk consisted of strong anion exchange (SAX) of 10-μm styrene divinylbenzene (SDB) particles embedded in Teflon, and...
Potassium-calcium decay system
Brian D. Marshall
1999, Book chapter, Encyclopedia of geochemistry
Potassium has three isotopes (see Potassium); potassium-40 ( 40K) is radioactive and decays to both calcium-40 ( 40Ca) and argon-40 ( 40Ar). The combined half-life of 40K is 1.25 billion years. The branched decay scheme of 40K is shown in Figure P33. It decays by β- decay to 40Ca and to 40Ar by both electron capture and...
Dating methods
Brian D. Marshall
1999, Book chapter, Encyclopedia of geochemistry
One of the greatest contributions of geochemistry to man's knowledge of the Earth and solar system has been the development and application of chemical and isotopic techniques used to measure the passage of time. Rates of geologic processes, rates of biological evolution, and contemporaneity of past events all depend on...
The hunt for Antarctic climate history
Peter Barker, Alan K. Cooper
1999, Antarctic Science (11) 273-273
No abstract available. ...
Vegetative resistance to flow in south Florida: Summary of vegetation sampling at sites NESRS3 and P33, Shark River Slough, November, 1996
Virginia Carter, Justin T. Reel, Nancy B. Rybicki, Henry A. Ruhl, Patricia T. Gammon, Jonathan K. Lee
1999, Open-File Report 99-218
The U.S. Geological Survey is one of many agencies participating in the effort to restore the South Florida Everglades. We are sampling and characterizing the vegetation at selected sites in the Everglades as part of a study to quantify vegetative flow resistance. The objectives of the vegetation sampling are (1)...
Vegetative resistance to flow in South Florida: Summary of vegetation sampling at sites NESRS3 and P33, Shark River Slough, April 1996
Virginia Carter, Henry A. Ruhl, Nancy B. Rybicki, Justin T. Reel, Patricia T. Gammon
1999, Open-File Report 99-187
The U.S. Geological Survey is one of many agencies participating in the effort to restore the south Florida Everglades. We are sampling and characterizing the vegetation at selected sites in the Everglades as part of a study to quantify vegetative flow resistance. The objectives of the vegetative sampling are (1)...
Results of time-domain electromagnetic soundings in Everglades National Park, Florida
D.V. Fitterman, Maria Deszcz-Pan, C.E. Stoddard
1999, Open-File Report 99-426
This report describes the collection, processing, and interpretation of time-domain electromagnetic soundings from Everglades National Park. The results are used to locate the extent of seawater intrusion in the Biscayne aquifer and to map the base of the Biscayne aquifer in regions where well coverage is sparse. The data show...
Biomass and vegetative characteristics of sawgrass grown in a tilting flume as part of a study of vegetative resistance to flow
Nancy B. Rybicki, Justin T. Reel, Henry A. Ruhl, Patricia T. Gammon, Virginia Carter, Jonathan K. Lee
1999, Open-File Report 99-230
The U.S. Geological Survey is studying vegetative resistance to flow in the south Florida Everglades as part of a multidisciplinary effort to restore the South Florida Ecosystem. In order to test the flow resistance of sawgrass, one of the dominant species in the Everglades, uniform, dense stands of sawgrass were...
Fire, red squirrels, whitebark pine, and Yellowstone grizzly bears
Shannon Podruzny, Daniel P. Reinhart, David J. Mattson
1999, Ursus (11) 131-138
Whitebark pine (Pinus albicaulis) habitats are important to Yellowstone grizzly bears (Ursus arctos) as refugia and sources of food. Ecological relationships between whitebark pine, red squirrels (Tamiasciurus hudsonicus), and grizzly bear use of pine seeds on Mt. Washburn in Yellowstone National Park, Wyoming, were examined during 1984-86. Following large-scale fires...
Stable isotopes and mineral resource investigations in the United States
Robert R. Seal, II
1999, Report
The elements oxygen, hydrogen, sulfur, and carbon are important constituents of hydrothermal ore-forming systems and the weathering processes of mineral deposits in the surficial environment. They also play key roles in volcanic activity, ecosystem dynamics, climate change, and hydrologic and atmospheric processes. Therefore, study of the stable isotopes of these...
Environmental processes that affect mineral deposits in the eastern United States
Robert R. Seal, II
1999, Report
A thorough understanding of the environmental processes that affect mineral deposits and mine wastes has become increasingly important as the Nation wrestles with how to meet our current demand for metals without compromising the environment and how to mitigate the damage caused by the mining practices of previous generations. Regulatory...
Progress toward characterization of juvenile materials in lunar pyroclastic deposits
Lisa R. Gaddis
Lisa Gaddis, Charles K. Shearer, editor(s)
1999, Book, Workshop on New Views of the Moon II: understanding the moon through the integration of diverse datasets: Flagstaff, Arizona, September 22-24, 1999
This report and related work describe progress toward remote characterization of the compositions of juvenile materials in the pyroclastic deposits located at Taurus-Littrow and J. Herschel....
Microbial, algal and fungal strategies for manganese oxidation at a Shade Township coal mine, Somerset County, Pennsylvania
E. I. Robbins, D.L. Brant, P.F. Ziemkiewicz
1999, Book, Mining and reclamation for the next millennium: proceedings of the 16th Annual National Meeting of the American Society for Surface Mining and Reclamation: proceedings of a conference held on August 13-19, 1999 in Scottsdale, Arizona
No abstract available....
A constructed wetland system for treatment of landfill leachate, Monroe County, New York
D.A.V. Eckhard, J.M. Surface, J.H. Peverly
1999, Book chapter, Constructed wetlands for the treatment of landfill leachates
No abstract available....
The Del Puerto Ophiolite: petrology and tectonic setting
Russell C. Evarts, Robert G. Coleman, Peter Schiffman
David L. Wagner, S.A. Graham, editor(s)
1999, Geologic field trips in Northern California: centennial meeting of the Cordilleran Section of the Geological Society of America (119) 136-149
Simulation of the potential responses of regional climate and surface processes in western North America to a canonical Heinrich event
S. W. Hostetler, P. J. Bartlein
Peter U. Clark, Robert S. Webb, Lloyd D. Keigwin, editor(s)
1999, Book chapter, Mechanisms of global climate change at millennial time scales
No abstract available....
