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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Sex assignment of lake sturgeon (Acipenser fluvescens) based on plasma sex hormone and vitellogenin levels
This study focused on identifying the sex of lake sturgeon by measuring the sex hormones estradiol and testosterone, and the phosphoprotein vitellogenin (Vtg) in blood plasma by radioimmunoassay and enzyme-linked immunosorbent assay, respectively, and evaluating these techniques as tools in lake sturgeon population management. Surveys of the St Clair River (SCR) lake sturgeon population have chara
Authors
J.M. Craig, D. M. Papoulias, M.V. Thomas, M.L. Annis, J. Boase
Status and trends of prey fish populations in Lake Superior, 2008
The Great Lakes Science Center has conducted annual daytime bottom trawl surveys of the Lake Superior nearshore (15-80 m bathymetric depth zone) every spring since 1978 to provide a long-term index of relative abundance and biomass of the fish community. Between May 5 and June 14, 2008, 58 stations were sampled around the perimeter of the lake with 12-m wide bottom trawls. Trawls were deployed cro
Authors
Owen T. Gorman, Lori M. Evrard, Gary A. Cholwek, Jill M. Falck, Daniel Yule
Status and trends of the Lake Huron deepwater demersal fish ommunity, 2008
The U.S.Geological Survey Great Lakes Science Center has conducted trawl surveys to assess annual changes in the deepwater demersal fish community of Lake Huron since 1973. Since 1992, surveys have been carried out using a 21 m wing trawl towed on-contour at depths ranging from 9 to 110 m on fixed transects. Sample sites include five ports in U.S. waters with less frequent sampling near Goderich,
Authors
Edward F. Roseman, Timothy P. O'Brien, Stephen C. Riley, Steve A. Farha, John R. French
Status of pelagic prey fishes and pelagic macroinvertebrates in Lake Michigan, 2008
Acoustic surveys were conducted in late summer/early fall during the years 1992-1996 and 2001-2008 to estimate pelagic prey fish biomass in Lake Michigan. Midwater trawling during the surveys provided a measure of species and size composition of the fish community for use in scaling acoustic data and providing species-specific abundance estimates. In 2005, we began sampling Mysis diluviana during
Authors
David M. Warner, Randall M. Claramunt, Jeffrey D. Holuszko, Timothy J. Desorcie
SToRM: A numerical model for environmental surface flows
SToRM (System for Transport and River Modeling) is a numerical model developed to simulate free surface flows in complex environmental domains. It is based on the depth-averaged St. Venant equations, which are discretized using unstructured upwind finite volume methods, and contains both steady and unsteady solution techniques. This article provides a brief description of the numerical approach se
Authors
Francisco J. Simoes
Strategic analysis for the MER Cape Verde approach
The Mars Exploration Rover Opportunity has recently completed a two year campaign studying Victoria Crater. The campaign culminated in a close approach of Cape Verde in order to acquire high resolution imagery of the exposed stratigraphy in the cliff face. The close approach to Cape Verde provided significant challenges for every subsystem of the rover as the rover needed to traverse difficult, un
Authors
Daniel Gaines, Paolo Belluta, Jennifer Herman, Pauline Hwang, Ryan Mukai, Dan Porter, Byron Jones, Eric Wood, John P. Grotzinger, Lauren A. Edgar, Alex Hayes, Trent M. Hare, Steve W. Squyres
Stream-network navigation in the U.S. Geological Survey stream stats web application
StreamStats is a U.S. Geological Survey Web-based geographic information systems application developed as a tool for water-resources planning and management, engineering design, and other applications. The primary functionality of StreamStats allows users to obtain drainage-basin boundaries, basin characteristics, and streamflow statistics for gaged and ungaged sites. Recently, tools that allow st
Authors
K. G. Ries, P. A. Steeves, J. D. Guthrie, A. H. Rea, D. W. Stewart
Strong Motion Instrumentation of Seismically-Strengthened Port Structures in California by CSMIP
The California Strong Motion Instrumentation Program (CSMIP) has instrumented five port structures. Instrumentation of two more port structures is underway and another one is in planning. Two of the port structures have been seismically strengthened. The primary goals of the strong motion instrumentation are to obtain strong earthquake shaking data for verifying seismic analysis procedures and str
Authors
M.J. Huang, A.F. Shakal
Surveillance and status of fish stocks in western Lake Erie, 2008
The Lake Erie Biological Station has conducted bottom trawl assessments of fish populations in western Lake Erie near East Harbor State Park, Ohio each summer and autumn since 1961. The catches of most age-0 forage fishes in 2008 were less than their 15-year means. Mean densities for five species exceeded the long term mean. Mean density of age-0 white perch Morone americana was more than double l
Authors
Michael T. Bur, William Edwards, Michael J. Porta, Martin A. Stapanian, Patrick Kočovský
The ecohealth assessment and ecological restoration division of urban water system in Beijing
Evaluating six main rivers and six lakes in Beihuan water system (BWS) and diagnosing the limiting factors of eco-health were conducted for the ecohealth assessment and ecological restoration division of urban water system (UWS) for Beijing. The results indicated that Jingmi River and Nanchang River were in a healthy state, the degree of membership to unhealthy were 0.358, 0.392, respectively; whi
Authors
J. Liu, M. Ma, F. Zhang, Z. Yang, Joseph L. Domagalski
The geologic relationships of industrial mineral deposits and asbestos in the western united states
In recent years, U.S. regulatory agencies have placed emphasis on identifying and regulating asbestos dust exposures in the mining environment, with a particular focus upon industrial mineral deposits in which asbestos occurs as an accessory mineral. Because asbestos minerals form in specific geologic environments, only certain predictable types of industrial mineral deposits can potentially host
Authors
B.S. VanGosen
The history of aggregate development in the Denver, CO area
At the start of the 20th century Denver's population was 203,795. Most streets were unpaved. Buildings were constructed of wood frame or masonry. Transport was by horse-drawn-wagon or rail. Statewide, aggregate consumption was less than 0.25 metric tons per person per year. One hundred years later Denver had a population of 2,365,345. Today Denver is a major metropolitan area at the crossroads of
Authors
W. H. Langer