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Publications

Publications from USGS science centers throughout the Southeast Region.

Filter Total Items: 10386

The factors controlling species density in herbaceous plant communities: An assessment The factors controlling species density in herbaceous plant communities: An assessment

This paper evaluates both the ideas and empirical evidence pertaining to the control of species density in herbaceous plant communities. While most theoretical discussions of species density have emphasized the importance of habitat productivity and disturbance regimes, many other factors (e.g. species pools, plant litter accumulation, plant morphology) have been proposed to be important...
Authors
J.B. Grace

Hourly and daily variation of sediment redox potential in tidal wetland sediments Hourly and daily variation of sediment redox potential in tidal wetland sediments

Variation of electrochemical oxidation-reduction (redox) potential was examined in surface salt march sediments under conditions of flooding and tidal simulation in mesocosms and field sites. Time series were generated of redox potential measured in sediment profiles at 2-10 cm depth using combination Pt-Ag/AgCl (ORP) electrodes. Redox potential data were acquired at rapid rates (1-55...

Induction of triploidy and tetraploidy in Nile tilapia, Oreochromis niloticus (L.) Induction of triploidy and tetraploidy in Nile tilapia, Oreochromis niloticus (L.)

Induction of triploidy and tetraploidy in Nile tilapia, Oreochromis niloticus, was investigated by heat shock, cold shock, hydrostatic pressure, and/or chemicals (cytochalasin A, B, and D). Additionally, efficacy of combined protocols was determined. Heat shock 10 min after fertilization induced triploidy when incubation temperature was 24 C but not when incubation temperature was 31 C...
Authors
A.-R.A. El Gamal, K. B. Davis, J.A. Jenkins, Torrans E. Les

Use of power analysis to develop detectable significance criteria for sea urchin toxicity tests Use of power analysis to develop detectable significance criteria for sea urchin toxicity tests

When sufficient data are available, the statistical power of a test can be determined using power analysis procedures. The term “detectable significance” has been coined to refer to this criterion based on power analysis and past performance of a test. This power analysis procedure has been performed with sea urchin (Arbacia punctulata) fertilization and embryological development data...
Authors
R.S. Carr, J.M. Biedenbach

Sodium cyanide hazards to fish and other wildlife from gold mining operations Sodium cyanide hazards to fish and other wildlife from gold mining operations

Highly toxic sodium cyanide (NaCN) is used increasingly by the international mining community to extract gold and other precious metals through milling of high grade ores and heap leaching of low grade ores. Of the 98 million kg cyanide (CN) consumed in North America in 1989, about 80% was used in gold mining (Knudson 1990). In Canada, more than 90% of the mined gold is extracted from...
Authors
R. Eisler, D. R. Clark, Stanley N. Wiemeyer, Charles J. Henny

Photoenhanced toxicity of a weathered oil on Ceriodaphnia dubia reproduction Photoenhanced toxicity of a weathered oil on Ceriodaphnia dubia reproduction

Traditionally, the toxic effects of petroleum have been investigated by conducting studies in the absence of ultraviolet radiation (UV). Photomediated toxicity is often not considered, and the toxic effects of an oil spill can be grossly underestimated. The toxicity of a weathered oil collected from a monitoring well at an abandoned oil field toCeriodaphnia dubia was examined in the...
Authors
R.D. Calfee, E. E. Little, L. Cleveland, M.G. Barron

Natural regeneration and growth of Taxodium distichum (L.) rich. In Lake Chicot, Louisiana after 44 years of flooding Natural regeneration and growth of Taxodium distichum (L.) rich. In Lake Chicot, Louisiana after 44 years of flooding

Lake Chicot, in south central Louisiana, USA, was created in 1943 by the impoundment of Chicot Bayou. Extensive establishment of woody seedlings occurred in the lake during a 1.5 year period, including the growing seasons of both 1986 and 1987, when the reservoir was drained for repair work on the dam. Study plots were established in September 1986 to document woody vegetation...
Authors
B. D. Keeland, W.H. Conner

Water resources data, South Carolina, water year 1999 Water resources data, South Carolina, water year 1999

Water resources data for the 1999 water year for South Carolina consist of records of stage, discharge, and water quality of streams; stage and contents of lakes and reservoirs; and ground-water levels. This report contains discharge records for 118 gaging stations; stage-only records for 38 gaging stations; stage and contents for 17 lakes and reservoirs; water quality for 42 gaging...
Authors
T.W. Cooney, P.A. Drewes, S.W. Ellisor, F. Melendez
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