Publications
This list of Water Resources Mission Area publications includes both official USGS publications and journal articles authored by our scientists. A searchable database of all USGS publications can be accessed at the USGS Publications Warehouse.
Filter Total Items: 18468
Comparison of purge and trap GC/MS and purgeable organic chloride analysis for monitoring volatile chlorinated hydrocarbons
A combined field and laboratory study was conducted to compare purge and trap gas chromatography/mass spectrometry (PT‐GC/MS) and purgeable organic chloride (POC1) analysis for measuring volatile chlorinated hydro‐carbons (VCH) in ground water. Distilled‐water spike and recovery experiments using 10 VCH indicate that at concentrations greater than 1 /ig/1 recovery is more than 80 percent for both
Authors
Larry B. Barber, E. Michael Thurman, Yoshi Takahashi, Mary C. Noriega
Riparian vegetation recovery patterns following stream channelization: A geomorphic perspective
Hundreds of kilometres of West Tennessee streams have been channelized since the turn of the century. After a stream is straightened, dredged, or cleared, basinwide ecologic, hydrologic, and geomorphic processes bring about an integrated, characteristic recovery sequence. The rapid pace of channel responses to channelization provides an opportunity to document and interpret vegetation recovery pat
Authors
Cliff R. Hupp
A reconnaissance study of herbicides and their metabolites in surface water of the midwestern united states using immunoassay and gas chromatography/mass spectrometry
Preemergent herbicides and their metabolites, particularly atrazine, deethylatrazine, and metolachlor, persisted from 1989 to 1990 in the majority of rivers and streams in the midwestern United States. In spring, after the application of herbicides, the concentrations of atrazine, alachlor, and simazine were frequently 3-10 times greater than the U.S. Environmental Protection Agency maximum contam
Authors
E. Michael Thurman, D. A. Goolsby, M. T. Meyer, M. S. Mills, M.L. Pomes, Dana W. Kolpin
Modeling transport in transient ground-water flow: An unacknowledged approximation
During unsteady or transient ground-water flow, the fluid mass per unit volume of aquifer changes as the potentiometric head changes, and solute transport is affected by this change in fluid storage. Three widely applied numerical models of two-dimensional transport partially account for the effects of transient flow by removing terms corresponding to the fluid continuity equation from the transpo
Authors
Daniel J. Goode
Pesticide residues in ground water of the San Joaquin Valley, California
A regional assessment of non-point-source contamination of pesticide residues in ground water was made of the San Joaquin Valley, an intensively farmed and irrigated structural trough in central California. About 10% of the total pesticide use in the USA is in the San Joaquin Valley. Pesticides detected include atrazine, bromacil, 2.4-DP, diazinon, dibromochloropropane, 1,2-dibromoethane, dicamba,
Authors
Joseph L. Domagalski, N. M. Dubrovsky
Bidirectional sulfate diffusion in saline-lake sediments: Evidence from Devils Lake, northeast North Dakota
Chemical and isotopic gradients in pore water in Devils Lake indicate that maximum rates of sulfate reduction occur between 1 and 3 cm depth in the bottom sediments. Dissolved sulfate diffuses into the sulfate-reduction zone upward from deeply buried saline pore water at an average rate of 1.4 x 10-5 μmol ⋅ cm-2 ⋅ s-1, and downward from the overlying water column at an average rate of 2.4 x 10-5 μ
Authors
S.C. Komor
Two-dimensional circulation modeling of the Pamlico River estuary, North Carolina
A two dimensional, vertically averaged, unsteady flow model was applied to a 50- kilometer reach of the Pamlico River estuary, North Carolina. The model computational grid, which consists of about 16,000 square cells, each 200 meters on a side, was developed from more than one million depth soundings. Information from a comprehensive data-collection network, including six water-level stations, six
Authors
G. L. Giese, Jerad Bales
Trophic interactions and direct physical effects control phytoplankton biomass and production in an estuary
San Francisco Bay has recently been invaded by the suspension-feeding clam Potamocorbula amurensis. Previous work has shown that phytoplankton biomass in the upper estuary is low (2-3 mg Chl a m-3) during seasonal periods of high river flow and short residence time and it is usually high (peak >30 mg Chl a m-3) during the summer-autumn seasons of low river flow and long residence time. However sin
Authors
A.E. Alpine, J. E. Cloern
Ground-water models cannot be validated
Ground-water models are embodiments of scientific hypotheses. As such, the models cannot be proven or validated, but only tested and invalidated. However, model testing and the evaluation of predictive errors lead to improved models and a better understanding of the problem at hand. In applying ground-water models to field problems, errors arise from conceptual deficiencies, numerical errors, and
Authors
Leonard F. Konikow, J. D. Bredehoeft
Effects of saline ground-water discharge on water quality of the Red River of the North, northeastern North Dakota
No abstract available.
Authors
M.L. Strobel, P.J. Gerla
Nitrate is a preferred electron acceptor for growth of freshwater selenate-respiring bacteria
An anaerobic, freshwater enrichment grew with either nitrate or selenate as an electron acceptor. With both ions present, nitrate reduction preceded selenate reduction. An isolate from the enrichment grew on either ion, but the presence of nitrate precluded the reduction of selenate. Stock cultures of denitrifiers grew anaerobically on nitrate but not on selenate.
Authors
Nisan A. Steinberg, Jodi Switzer Blum, Lawrence Hochstein, Ronald S. Oremland