Conference Papers
Science Quality and Integrity
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The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
Browse almost 5,000 conference papers authored by our scientists and refine search by topic, location, year, and advanced search.
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Transferability of tubifex limiting factor models Transferability of tubifex limiting factor models
Dense populations of T. tubifex are generally associated with habitats dominated by fine sediments and enriched organic material (e.g. Krueger, 2002). Management of whirling disease positive systems is entering a new phase where channel modifications are being implemented to reduce or isolate this type of habitat. These management actions have the potential to cause new areas of sediment
Authors
James W. Terrell, Robert T. Milhous
Preparing for THEMIS controlled global Mars mosaics Preparing for THEMIS controlled global Mars mosaics
We have begun work to prepare for producing controlled 2001 Mars Odyssey THEMIS infrared (IR) and visible (VIS) global mosaics of Mars. This effort is being coordinated with colleagues from Arizona State University and on the THEMIS team who plan to address radiometric issues in making such mosaics. We are concentrating on geometric issues. Several areas of investigation are now in...
Authors
Brent A. Archinal, Lynn A. Weller, Stuart C. Sides, Glen E. Cushing, Randolph L. Kirk, Laurence A. Soderblom, T. C. Duxbury
A Floristic Quality Assessment system for the coastal prairie of Louisiana A Floristic Quality Assessment system for the coastal prairie of Louisiana
Evaluation systems to assess the biotic integrity of plant communities exist for some ecosystems, but not the increasingly rare coastal prairies of Louisiana. A list of plant species occurring in Louisiana's coastal prairie was created and coefficients of conservatism (C) were assigned for each species. A Floristic Quality Index (FQI), which is calculated using the C values provided by a...
Authors
Larry K. Allain, Latimore Smith, Charles Allen, Malcolm Vidrine, James B. Grace
Digital elevation extraction from multiple MTI data sets Digital elevation extraction from multiple MTI data sets
The Digital Elevation Model (DEM) extraction process traditionally uses a stereo pair of aerial photographs that are sequentially captured using an airborne metric camera. Standard DEM extraction techniques have been naturally extended to utilize satellite imagery. However, the particular characteristics of satellite imaging can cause difficulties in the DEM extraction process. The...
Authors
Jeffrey A. Mercier, Robert A. Schowengerdt, James C. Storey, Jody L. Smith
Survival and growth of bottomland hardwood seedlings and natural woody invaders near forest edges Survival and growth of bottomland hardwood seedlings and natural woody invaders near forest edges
Several oak species are frequently planted for reforestation projects in the Lower Mississippi Alluvial Valley (LMAV), but the success of these plantings has been variable. The survival and growth of planted seed or seedlings are affected by a variety of factors, including competition, herbivory, site preparation, precipitation, planting stock quality, and planting techniques. We...
Authors
John W. McCoy, Bobby D. Keeland, Kristi Wharton
Ground-nesting marine birds and potential for human disturbance in Glacier Bay National Park Ground-nesting marine birds and potential for human disturbance in Glacier Bay National Park
Glacier Bay National Park and Preserve contains a diverse assemblage of marine birds that use the area for nesting, foraging and molting. The abundance and diversity of marine bird species in Glacier Bay is unmatched in the region, due in part to the geomorphic and successional characteristics that result in a wide array of habitat types (Robards and others, 2003). The opportunity for...
Authors
Mayumi L. Arimitsu, Marc D. Romano, John F. Piatt
A high resolution record of chlorine-36 nuclear-weapons-tests fallout from Central Asia A high resolution record of chlorine-36 nuclear-weapons-tests fallout from Central Asia
The Inilchek Glacier, located in the Tien Shan Mountains, central Asia, is unique among mid-latitude glaciers because of its relatively large average annual accumulation. In July 2000, two ice cores of 162 and 167 meters (m) in length were collected from the Inilchek Glacier for (chlorine-36) 36Cl analysis a part of a collaborative international effort to study the environmental changes...
Authors
J.R. Green, L.D. Cecil, H.-A. Synal, J. Santos, K.J. Kreutz, C.P. Wake
A molecular comparison of Alaskan and North East Atlantic Halicondria panicea (Pallas 1766) (Porifera: Demospongiae) A molecular comparison of Alaskan and North East Atlantic Halicondria panicea (Pallas 1766) (Porifera: Demospongiae)
The intraspecific relationships between populations of Alaskan Halichondria cf. panicea are the subjects of ongoing research. In this study we compare CO1 sequences of Alaskan Halichondria cf. panicea with North East Atlantic Halichondria panicea and its sister species Halichondria bowerbanki. Alaskan Halichondria cf. panicea form a well-supported sister group to the European...
Authors
Dirk Erpenbeck, Anne L. Knowlton, Sandra L. Talbot, Ray C. Highsmith, Rob W.M. van Soest
A project summary: Water and energy budget assessment for a non-tidal wetland in the Sacramento-San Joaquin delta A project summary: Water and energy budget assessment for a non-tidal wetland in the Sacramento-San Joaquin delta
The methods used to obtain universal cover coefficient (Kc) values for a non-tidal restored wetland in the Sacramento-San Joaquin river delta, US, during the summer of the year 2002 and to investigate possible differences during changing wind patterns are described. A micrometeorological tower over the wetland was established to quantify actual evapotranspiration (ETa) rates and surface...
Authors
Frank E. Anderson, R.L. Snyder, U.K.T. Paw, Judith Z. Drexler
A prototype for understanding the effects of TMDL standards: Tying property values to sediment loads in the Lake Tahoe Basin A prototype for understanding the effects of TMDL standards: Tying property values to sediment loads in the Lake Tahoe Basin
The Federal Clean Water Act (Section 303(d)) mandates that states develop Total Maximum Daily Load (TMDL) plans for water bodies that are on the Section 303(d) list. To be placed on the 303(d) list, a water body must be found to have water quality conditions that limit its ability to meet its designated beneficial uses. The TMDL for a water body is defined in 40 CFR 130 as the sum of...
Authors
J.C. Tracy, R. Bernknopf, W. Forney, K. Hill
A South San Francisco Bay sediment budget: Wetland restoration and potential effects on phytoplankton blooms A South San Francisco Bay sediment budget: Wetland restoration and potential effects on phytoplankton blooms
No abstract available.
Authors
G.G. Shellenbarger, D. H. Schoellhamer, M. A. Lionberger
A web-enabled system for integrated assessment of watershed development A web-enabled system for integrated assessment of watershed development
Researchers at Virginia Tech have put together the primary structure of a web enabled integrated modeling system that has potential to be a planning tool to help decision makers and stakeholders in making appropriate watershed management decisions. This paper describes the integrated system, including data sources, collection, analysis methods, system software and design, and issues of...
Authors
R. Dymond, V. Lohani, B. Regmi, R. Dietz