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Publications

Publications from USGS science centers throughout the Southeast Region.

Filter Total Items: 9969

A geographic information systems technique for monitoring contaminants in Galveston Bay, Texas

A geographic information system (GIS) was used to compile a series of databases containing details concerning metal contamination and pollution sources to study their impacts on the Galveston Bay (TX) ecosystem. Using these databases, a series of maps with various overlays was created with ARC/INFO software. These maps allowed patterns of spatial distribution of numerous variables to be easily vis
Authors
Marcia McNiff, P.F. Roscigno, W. Ji

Preliminary analysis of spectral data collected for the purpose of wetland discrimination

No abstract available.
Authors
Elijah Ramsey III, R. Spell, James B. Johnston

Knowledge-based gis approaches: A prototype expert system for wetland resource management

No abstract available.
Authors
Wei Ji, James B. Johnston, Marcia McNiff, Loyd C. Mitchell

Ecology and management of postbreeding waterfowl

No abstract available.
Authors
William L. Hohman, C. Davison Ankney, David H. Gordon

Size bias in traditional analyses of substitutive competition experiments

The objective of this study was to examine the claim that traditional measures of competitive performance in substitutive experiments are biased towards larger plants. Results from a three-year diallele experiment of 6 marsh plant species were analyzed using both Relative Yields (a traditional analysis) and the Relative Efficiency Index (a recently proposed analysis presumed to be size-independent
Authors
James B. Grace, Janet R. Keough, Glenn R. Guntenspergen

Regional evaluations of acid deposition effects on forests: Eastern spruce-fir

Having reviewed the results of the Integrated Forest Study (IFS) project, we now try to place the results in a larger perspective by very briefly summarizing acid deposition effects and their potential role in forest health in the several forest types represented in the IFS project. This chapter gives brief overviews of the situation in eastern spruce-fir, eastern hardwood, and southern pine fores
Authors
A. H. Johnson, A. J. Friedland, E. K. Miller, J. J. Battles, Thomas G. Huntington, D. R. Vann, G. R. Strimbeck

Flow cytometry, morphometry and histopathology as biomarkers of benzo[a]pyrene exposure in brown bullheads (ameiurus nebulosus)

Brown bullheads were given a single intraperitoneal dose of 0, 5, 25 or 125 mg kg−1 benzo[a]pyrene (BaP), a carcinogenic polycyclic aromatic hydrocarbon, and evaluated over 18 months. Flow cytometric analyses of hepatocyte DNA content indicated an increase in DNA synthesis in BaP-exposed fish prior to day 14 post-exposure. Thereafter, all flow cytometric variables returned to initial levels. Histo
Authors
Andrew W. Grady, Ronald M. McLaughlin, Charles W. Caldwell, Christopher J. Schmitt, David L. Stalling

Herbicide and nitrate variation in alluvium underlying a cornfield at a site in Iowa County, Iowa

A hydrologic investigation to determine vertical and seasonal variation of atrazine, alachlor, cyanazine, and nitrate at one location and to relate the variation to ground-water movement in the Iowa River alluvium was conducted in Iowa County, Iowa, from March 1986 to December 1987. Water samples were collected at discrete intervals through the alluvial sequence from the soil zone to the base of t
Authors
S. J. Kalkhoff, M.G. Detroy, K. Cherryholmes, R.L. Kuzniar

Alternate reproductive strategies in the California gull

We analysed 6 years of reproduction data for 176 California gulls (Larus californicus) surviving from 1980 to 1988. Using a statistical model adapted from Rao's (1958) and Tucker's (1966) generalized growth curve analysis, we reconstructed the reproductive patterns of gulls aged from 0 to 26 years. Individuals were highly consistent in following one of two patterns of reproduction. In a primary pa
Authors
Bruce H. Pugesek, P. Wood

Selective dipnetting of largemouth bass during electrofishing

We electrofished 10 north‐central Texas reservoirs from 1987 through 1990 by either dipnetting all electroshocked fish (intensive dipnetting) or selectively dipnetting only fish visually identified as largemouth bass Micropterus salmoides. We compared selected indices of population structure (proportional stock density, relative stock density, and young–adult ratio) and abundance (catch per unit e
Authors
Daniel J. Twedt, W. Clell Guest, Bobby W. Farquhar