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: 18464
An improved method for quantifying soil macroporosity
Quantitative information on macroporosity is needed to predict water flow and solute transport in field soils. A method was developed for determining the number, shape, and size distribution of soil macropores. Horizontal serial sections sawed from paraffin-impregnated soil cores were photographed under ultraviolet (UV) light. Anthracene, mixed with the paraffin, fluoresces a bright bluish white u
Authors
V. R. Vermeul, J.D. Istok, A. L. Flint, J.L. Pikul Jr.
A Geographic Information System procedure to quantify drainage-basin characteristics
The Basin Characteristics System (BCS) has been developed to quantify characteristics of a drainage basin. The first of four main BCS processing steps creates four geographic information system (GIS) digital maps representing the drainage divide, the drainage network, elevation contours, and the basin length. The drainage divide and basin length are manually digitized from 1:250,000-scale topogra
Authors
David A. Eash
A laboratory and field evaluation of a portable immunoassay test for triazine herbicides in environmental water samples
The usefulness and sensitivity, of a portable immunoassay test for the semiquantitative field screening of water samples was evaluated by means of laboratory and field studies. Laboratory results indicated that the tests were useful for the determination of atrazine concentrations of 0.1 to 1.5 μg/L. At a concentration of 1 μg/L, the relative standard deviation in the difference between the regres
Authors
P.A. Schulze, P. D. Capel, P. J. Squillace, D.R. Helsel
Hydrologic budget and nitrogen distribution for an agricultural study plot in claypan soil and glacial till near Centralia, Mo.--May 1991 to May 1992
No abstract available.
Authors
Brian P. Kelly, L.N. Plummer
Understanding the toxicity of contaminants in sediments: beyond the bioassay-based paradigm
No abstract available.
Authors
Samuel N. Luoma, James L. Carter
Aspects of the biogeochemistry of methane in Mono Lake and the Mono Basin of California
Above-ambient levels of methane and higher hydrocarbons were detected in the atmosphere of the Mono Basin. These gases emanated from several different sources, including natural gas seeps (thermogenic and biogenic), and methanogenic activity in sediments. Seeps were distributed over nearly 33% of the lake bottom and were also present in the exposed former lakebed. They originated from one or more
Authors
Ronald S. Oremland, Laurence G. Miller, Charles Colbertson, S.W. Robinson, Richard L. Smith, D. R. Lovley, Michael J. Whiticar, G. King, Ronald P. Kiene, Niels Iversen, Melinda Sargent
Ground-water models: Validate or invalidate
The word validation has a clear meaning to both the scientific community and the general public. Within the scientific community the validation of scientific theory has been the subject of philosophical debate. The philosopher of science, Karl Popper, argued that scientific theory cannot be validated, only invalidated. Popper’s view is not the only opinion in this debate; however, many scientists
Authors
J. D. Bredehoeft, Leonard F. Konikow
Environmental tracers for age dating young ground water
No abstract available.
Authors
L.N. Plummer, R. L. Michel, E.M. Thurman, Pierre D. Glynn
Influence of redox environment and aqueous speciation on metal transport in groundwater: Preliminary results of tracer injection studies
No abstract available.
Authors
J. Davis, Kent D. Becher, B.A. Rea, A.S. Maest, S. P. Garabedian
Modelling within the stream-catchment continuum
No abstract available.
Authors
Kenneth E. Bencala, John H. Duff, Judson W. Harvey, A. P. Jackman, F.J. Triska
Tidal, Residual, Intertidal Mudflat (TRIM) Model and its Applications to San Francisco Bay, California
A numerical model using a semi-implicit finite-difference method for solving the two-dimensional shallow-water equations is presented. The gradient of the water surface elevation in the momentum equations and the velocity divergence in the continuity equation are finite-differenced implicitly, the remaining terms are finite-differenced explicitly. The convective terms are treated using an Eulerian
Authors
R. T. Cheng, V. Casulli, J. W. Gartner
Nitrogen isotopes as indicators of nitrate sources in Minnesota sand-plain aquifers
Nitrate concentrations in excess of national drinking-water standards (10 mg/1 as N) are present in certain sand-plain aquifers in central Minnesota. To investigate nitrate sources in the aquifers, nitrogen-isotope values of nitrate (δ15NNO3No3) were measured in shallow ground water from 51 wells in five land-use settings. The land-use settings and corresponding average nitrate concentrations (as
Authors
Stephen C. Komor, Henry W. Anderson