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Publications

These publications showcase the significant science conducted in our Science Centers.

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Dispersal Dispersal

The ability of species to migrate and disperse is a trait that has interested ecologists for many years. Now that so many species and ecosystems face major environmental threats from habitat fragmentation and global climate change, the ability of species to adapt to these changes by dispersing, migrating, or moving between patches of habitat can be crucial to ensuring their survival...

Apparent chlorofluorocarbon age of ground water of the shallow aquifer system, Naval Weapons Station Yorktown, Yorktown, Virginia Apparent chlorofluorocarbon age of ground water of the shallow aquifer system, Naval Weapons Station Yorktown, Yorktown, Virginia

Apparent ages of ground water are useful in the analysis of various components of flow systems, and results of this analysis can be incorporated into investigations of potential pathways of contaminant transport. This report presents the results of a study in 1997 by the U.S. Geological Survey (USGS), in cooperation with the Naval Weapons Station Yorktown, Base Civil Engineer...
Authors
David L. Nelms, George E. Harlow, Allen R. Brockman

An evaluation of borehole flowmeters used to measure horizontal ground-water flow in limestones of Indiana, Kentucky, and Tennessee, 1999 An evaluation of borehole flowmeters used to measure horizontal ground-water flow in limestones of Indiana, Kentucky, and Tennessee, 1999

Three borehole flowmeters and hydrophysical logging were used to measure ground-water flow in carbonate bedrock at sites in southeastern Indiana and on the west-central border of Kentucky and Tennessee. The three flowmeters make point measurements of the direction and magnitude of horizontal flow, and hydrophysical logging measures the magnitude of horizontal flowover an interval. The...
Authors
John T. Wilson, Wayne A. Mandell, Frederick L. Paillet, E. Randall Bayless, Randall T. Hanson, Peter M. Kearl, William B. Kerfoot, Mark W. Newhouse, William H. Pedler

Utility of splenic macrophage aggregates as an indicator of fish exposure to degraded environments Utility of splenic macrophage aggregates as an indicator of fish exposure to degraded environments

The utility of splenic macrophage aggregates (MAs) as an indicator of fish exposure to degraded environments was evaluated in several species of estuarine fishes as part of the Environmental Protection Agency's Environmental Monitoring and Assessment Program–Estuaries (EMAP-E). Using image analysis, we measured the number and mean size of MAs per square millimeter on tissue sections of...
Authors
J.W. Fournie, J.K. Summers, L.A. Courtney, V.D. Engle, V. S. Blazer

Guidance of yearling shortnose and pallid sturgeon using vertical bar rack and louver arrays Guidance of yearling shortnose and pallid sturgeon using vertical bar rack and louver arrays

Some populations of shortnose sturgeon Acipenser brevirostrum and pallid sturgeon Scaphirhynchus albus have been divided by hydroelectric dams, and migration downstream past the dams likely continues. No protection for downstream migrants is presently available, and the behavior of sturgeon to guidance structures has not been studied. We conducted experiments in a 5.4-m-long × 1.5-m-wide...
Authors
B. Kynard, Martin Horgan

Factors influencing the nitrification efficiency of fluidized bed filter with a plastic bead medium Factors influencing the nitrification efficiency of fluidized bed filter with a plastic bead medium

The performance of fluidized bed nitrification filters charged with 2×4 ABS plastic beads (specific gravity 1.06) was evaluated. Three unique bed-height to diameter ratios were established, in triplicate, using column diameters of 12.7, 15.2 and 17.8 cm. Filters received water spiked with recycled nutrients and ammonia (TAN), from one of the three 500 l feed tank system. With daily...
Authors
S. I. Sandu, G. D. Boardman, Barnaby J. Watten, B. L. Brazil

Effects of dissolved carbon dioxide on the physiology and behavior of fish artificial streams Effects of dissolved carbon dioxide on the physiology and behavior of fish artificial streams

A new technology for treating waters contaminated with acid mine drainage involves the dissolution of limestone particles using carbon dioxide at pressures above ambient. Because of the fish health risks associated with episodes of high carbon dioxide levels in treated waters, we subjected three species of fish, brook trout (Salvelinus fontinalis), slimy sculpin (Cottus cognatus), and...
Authors
R. M. Ross, W. F. Krise, Lori A. Redell, R. M. Bennett

Sensitivity of Atlantic salmon eggs to mechanical shock during the first six hours after fertilization Sensitivity of Atlantic salmon eggs to mechanical shock during the first six hours after fertilization

Eggs from six domestic adult Atlantic salmon Salmo salar and six sea-run kelts (wild adults held over for a second spawning season) were tested at 0.5 to 6 h after fertilization for sensitivity to mechanical shock produced by dropping eggs from measured heights. Estimates of drop height and force causing 10% (lethal tolerance, LT90) and 25% (LT75) mortality were used to project egg...
Authors
W. F. Krise

PCR-based assays for the fish pathogen Aeromonas salmonicida: Further evaluation and validation of three PCR primer sets with infected fish PCR-based assays for the fish pathogen Aeromonas salmonicida: Further evaluation and validation of three PCR primer sets with infected fish

Two Aeromonas salmonicida-specific polymerase chain reaction (PCR) tests and 1 A. salmonicida subsp. salmonicida-specific PCR test were used to screen salmonid populations that were either overtly or covertly infected with A. salmonicida subsp. salmonicida. It was demonstrated that these PCR assays could be used to replace the biochemical testing currently employed to confirm the...
Authors
H.K. Byers, R. C. Cipriano, N. Gudkovs, J Crane . St
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