Conference Papers
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Browse almost 5,000 conference papers authored by our scientists and refine search by topic, location, year, and advanced search.
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Long-term consequences of variation in timing and manner of fry introduction on juvenile Atlantic salmon (Salmo salar) growth, survival, and life-history expression
We tested the influence of introduction time and the manner of introduction on growth, survival, and life-history expression of Atlantic salmon (Salmo salar). Introduction treatments included three fry stocking times and stream rearing of embryos. Despite poor growth conditions during the early stocking period, early-stocked fish were larger throughout the entire study period, likely the result of
Authors
B. H. Letcher, T. Dubreuil, M. J. O'Donnell, M. Obedzinski, K. Griswold, K.H. Nislow
Measuring mercury and other elemental components in tree rings
There has been considerable interest in measuring heavy metal pollution, such as mercury, using tree ring analysis. Since 1970, this method has provided a historical snapshot of pollutant concentrations near hazardous waste sites. Traditional methods of analysis have long been used with heavy metal pollutants such as mercury. These methods, such as atomic fluorescence and laser ablation, are somet
Authors
C. Gillan, W.A. Hollerman, T.W. Doyle, T.E. Lewis
Measuring mercury and other elemental components in tree rings
There has been considerable interest in measuring heavy metal pollution, such as mercury, using tree ring analysis. Since 1970, this method has provided a historical snapshot of pollutant concentrations near hazardous waste sites. Traditional methods of analysis have long been used with heavy metal pollutants such as mercury. These methods, such as atomic fluorescence and laser ablation, are somet
Authors
C. Gillan, W.A. Hollerman, T.W. Doyle, T.E. Lewis
Methods and guidelines for effective model calibration
This paper briefly describes nonlinear regression methods, a set of 14 guidelines for model calibration, how they are implemented in and supported by two public domain computer programs, and a demonstration and a test of the methods and guidelines. Copyright ASCE 2004.
Authors
M. C. Hill
Methods for determining manning's coefficients for Illinois streams
Determination of Manning's coefficient, n, for natural streams remains a challenge in practices. One source for determining the n-values that has received practitioners' attention is presenting the n-values determined from field data (measured discharge and water-surface slope) in combination of photographs and site descriptions (ancillary information). Further improvements in the visual approach
Authors
D.T. Soong, T.M. Halfar, M.A. Jupin, L.A. Wobig
Migration of dispersive GPR data
Electrical conductivity and dielectric and magnetic relaxation phenomena cause electromagnetic propagation to be dispersive in earth materials. Both velocity and attenuation may vary with frequency, depending on the frequency content of the propagating energy and the nature of the relaxation phenomena. A minor amount of velocity dispersion is associated with high attenuation. For this reason, meas
Authors
M.H. Powers, C.P. Oden
Mineralogical and geochemical controls on the release of trace elements from slag produced by base- and precious-metal smelting at abandoned mine sites
Slag collected from smelter sites associated with historic base-metal mines contains elevated concentrations of trace elements such as Cu, Zn and Pb. Weathering of slag piles, many of which were deposited along stream banks, potentially may release these trace elements into the environment. Slags were sampled from the Ely and Elizabeth mines in the Vermont copper belt, from the copper Basin mining
Authors
N.M. Piatak, R.R. Seal, J. M. Hammarstrom
Modeling a three-dimensional river plume over continental shelf using a 3D unstructured grid model
River derived fresh water discharging into an adjacent continental shelf forms a trapped river plume that propagates in a narrow region along the coast. These river plumes are real and they have been observed in the field. Many previous investigations have reported some aspects of the river plume properties, which are sensitive to stratification, Coriolis acceleration, winds (upwelling or downwell
Authors
R. T. Cheng, V. Casulli
Modeling the Death Valley regional ground-water flow system
The development of a regional ground-water flow model of the Death Valley region in the southwestern United States is discussed in the context of the fourteen guidelines of Hill. This application of the guidelines demonstrates how they may be used for model calibration and evaluation, and to direct further model development and data collection.
Authors
F. A. D'Agnese, C.C. Faunt, M. C. Hill
Modification of pure oxygen absorption equipment for concurrent stripping of carbon dioxide
The high solubility of carbon dioxide precludes significant desorption within commercial oxygen absorption equipment. This operating characteristic of the equipment limits its application in recirculating water culture systems despite its ability to significantly increase allowable fish loading rates (kg/(L min)). Carbon dioxide (DC) is typically removed by air stripping. This process requires a s
Authors
B.J. Watten, P.L. Sibrell, G.A. Montgomery, S.M. Tsukuda
Monitoring radionuclide contamination in the unsaturated zone - Lessons learned at the Amargosa Desert Research Site, Nye County, Nevada
Contaminant-transport processes are being investigated at the U.S. Geological Survey’s Amargosa Desert Research Site (A DRS), adjacent to the Nation’s first commercial disposal facility for low-level radioactive waste. Gases containing tritium and radiocarbon are migrating through a 110-m thick unsaturated zone from unlined trenches that received waste from 1962 to 1992. Results relevant to long-
Authors
David A. Stonestrom, Jared D. Abraham, Brian J. Andraski, Ronald J. Baker, C. Justin Mayers, Robert L. Michel, David E. Prudic, Robert G. Striegl, Michelle Ann Walvoord