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: 18465
Dynamics of nutrient cycling and related benthic nutrient and oxygen fluxes during a spring phytoplankton bloom in South San Francisco Bay (USA)
Benthic oxygen uptake and nutrient releases of N, P and Si were measured weekly at 2 sites in South San Francisco Bay around the 1996 spring bloom. Exchanges across the sediment-water interface were estimated from whole core incubations performed in the laboratory at in situ temperature and in dark. Fluxes changed significantly on a weekly time scale. Over a period of 15 wk the fluxes of dissolved
Authors
C. Grenz, J. E. Cloern, S.W. Hager, B.E. Cole
Effects of topography and soil properties on recharge at two sites in an agricultural field
Field experiments were conducted from 1992 to 1995 to estimate ground water recharge rates at two sites located within a 2.7-hectare agricultural field. The field lies in a sand plain setting in central Minnesota and is cropped continuously in field corn. The sites are located at a topographically high (upland) site and a topographically low (lowland) site in an effort to quantify the effects of d
Authors
G. N. Delin, R. W. Healy, M.K. Landon, J.K. Böhlke
Diagenetic fate of organic contaminants on the Palos Verdes Shelf, California
Municipal wastes discharged through deepwater submarine outfalls since 1937 have contaminated sediments of the Palos Verdes Shelf. A site approximately 6–8 km downcurrent from the outfall system was chosen for a study of the diagenetic fate of organic contaminants in the waste-impacted sediments. Concentrations of three classes of hydrophobic organic contaminants (DDT+metabolites, polychlorinated
Authors
R.P. Eganhouse, J. Pontolillo, T.J. Leiker
Spatial and temporal variability of picocyanobacteria Synechococcus sp. in San Francisco Bay
We collected samples monthly, from April to August 1998, to measure the abundance of autotrophic picoplankton in San Francisco Bay. Samples taken along a 160-km transect showed that picocyanobacteria (Synechococcus sp.) was a persistent component of the San Francisco Bay phytoplankton in all the estuarine habitats, from freshwater to seawater and during all months of the spring-summer transition.
Authors
X. Ning, J. E. Cloern, B.E. Cole
Stable isotope systematics of sulfate minerals
Stable isotope studies of sulfate minerals are especially useful for unraveling the geochemical history of geological systems. All sulfate minerals can yield sulfur and oxygen isotope data. Hydrous sulfate minerals, such as gypsum, also yield oxygen and hydrogen isotope data for the water of hydration, and more complex sulfate minerals, such as alunite and jarosite also yield oxygen and hydrogen i
Authors
Robert R. Seal, Charles N. Alpers, Robert O. Rye
Water movement through a thick unsaturated zone underlying an intermittent stream in the western Mojave Desert, southern California, USA
Previous studies indicated that small amounts of recharge occur as infiltration of intermittent streamflow in washes in the upper Mojave River basin, in the western Mojave Desert, near Victorville, California. These washes flow only a few days each year after large storms. To reach the water table, water must pass through an unsaturated zone that is more than 130 m thick. Results of this study, do
Authors
J. A. Izbicki, J. Radyk, R. L. Michel
Stream chemistry modeling of two watersheds in the Front Range, Colorado
We investigated the hydrologic, geochemical, and biogeochemical controls on stream chemical composition on the Green Lakes Valley and Andrews Creek watersheds using the alpine hydrochemical model (AHM). Both sites had comparable data sets from 1994 and 1996, including high‐resolution spatial data and high‐frequency time series of hydrology, geochemistry, and meteorology. The model of each watershe
Authors
Thomas Meixner, Roger C. Bales, Mark W. Williams, Donald H. Campbell, Jill S. Baron
Associations among fish assemblage structure and environmental variables in Willamette Basin streams, Oregon
As part of the U.S. Geological Survey's National Water-Quality Assessment Program, fish were collected from 24 selected stream sites in the Willamette Basin during 1993-1995 to determine the composition of the fish assemblages and their relation to the chemical and physical environment. Variance in fish relative abundance was greater among all sites than among spatially distinct reaches within a s
Authors
Ian R. Waite, Kurt D. Carpenter
Relation of pathways and transit times of recharge water to nitrate concentrations using stable isotopes
Oxygen and hydrogen stable isotope values of precipitation, irrigation water, soil water, and ground water were used with soil-moisture contents and water levels to estimate transit times and pathways of recharge water in the unsaturated zone of a sand and gravel aquifer. Nitrate-nitrogen (nitrate) concentrations in ground water were also measured to assess their relation to seasonal recharge. Sta
Authors
M.K. Landon, G. N. Delin, S.C. Komor, C.P. Regan
Rice pesticide concentrations in the Colusa Basin Drain and the Sacramento River, California, 1990-1993
The pesticides molinate, thiobencarb, and carbofuran are applied to rice (Oryza sativa L.) fields in the Sacramento Valley, California, each year during April through June. These pesticides are of concern because of their adverse effects on water quality and their potential adverse effects on aquatic life. Therefore, the California Regional Water Quality Control Board (CRWQCB) mandated the holding
Authors
K.L. Crepeau, K.M. Kuivila
Change in field turbidity and trace element concentrations during well purging
Various physical and chemical properties were monitored sequentially in the field during well purging as indicators of stabilization of the composition of the water in the well. Turbidity was monitored on site during purging of oxic water from three wells with screened intervals open to an unconfined aquifer system in the Coastal Plain of southern New Jersey to determine if stabilization of turbid
Authors
J. Gibs, Zoltan Szabo, T. Ivahnenko, F.D. Wilde
Analysis of atrazine and four degradation products in the pore water of the vadose zone, central Indiana
A new method is described for the analysis of atrazine and four of its degradation products (desethylatrazine, deisopropylatrazine, didealkylatrazine, and hydroxyatrazine) in water. This method uses solid- phase extraction on a graphitized carbon black cartridge, derivatization of the eluate with N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide (MTBSTFA), and analysis by gas chromatography/m
Authors
S.Y. Panshin, D.S. Carter, E.R. Bayless