Measurement of nitrous oxide reductase activity in aquatic sediments
L.G. Miller, Ronald S. Oremland, S. Paulsen
1986, Applied and Environmental Microbiology (51) 18-24
Denitrification in aquatic sediments was measured by an N2O reductase assay. Sediments consumed small added quantities of N2O over short periods (a few hours). In experiments with sediment slurries, N2O reductase activity was inhibited by O2, C2H2, heat treatment, and by high levels of nitrate (1 mM) or sulfide (10...
Recovering fresh water stored in saline limestone aquifers
M. L. Merritt
1986, Ground Water (24) 516-529
Numerical modeling techniques are used to examine the hydrogeologic, design, and management factors governing the recovery efficiency of subsurface fresh-water storage. The modeling approach permitted many combinations of conditions to be studied. A sensitivity analysis was used that consisted of varying certain parameters while keeping constant as many other parameters...
Coincidence and spatial variability of geology, soils, and vegetation, Mill Run watershed, Virginia
C.G. Olson, C.R. Hupp
1986, Earth Surface Processes and Landforms (11) 619-629
The Mill Run watershed is a structurally‐controlled synclinal basin on the eastern limb of the Massanutten Mountain complex of northwestern Virginia. Bedrock contacts are obscured by coarse sandstone debris from exposures near basin divides. Colluvium blankets more than half the basin, masking geomorphic surfaces, affecting vegetation...
Management of the life and death of an earth-science database: some examples from geotherm
J. D. Bliss
1986, Computers & Geosciences (12) 199-205
Productive earth-science databases require managers who are familiar with and skilled at using available software developed specifically for database management. There also should be a primary user with a clearly understood mission. The geologic phenomenon addressed by the database must be sufficiently understood, and adequate appropriate data must be available...
Resurgence of submersed aquatic macrophytes in the tidal Potomac River, Maryland, Virginia, and the District of Columbia
V. Carter, N. Rybicki
1986, Estuaries (9) 368-375
A 1978–81 survey of submersed aquatic macrophytes in the tidal Potomac River showed that there were virtually no plants in the freshwater tidal river between Chain Bridge and Quantico, Virginia, decades after the disappearance of plants in the late 1930’s. Plant populations were monitored in subsequent years (1983–85) using qualitative...
Water solubility enhancement of some organic pollutants and pesticides by dissolved humic and fulvic acids
Cary T. Chiou, Ronald L. Malcolm, Terry I. Brinton, Daniel E. Kile
1986, Environmental Science & Technology (20) 502-508
No abstract available....
CONCEPTUAL DESIGN OF THE SURFACE WATER COMPONENT OF THE NATIONAL WATER QUALITY ASSESSMENT (NAWQA) PROGRAM.
Robert M. Hirsch
1986, Conference Paper, Oceans Conference Record (IEEE)
The US Geological Survey started, in a pilot phase, a program to provide nationally consistent information on the status and trends in the quality of the nation's fresh water. The program also intends to identify and describe the relationships between both the status and trends in water quality as they...
ANALYSIS OF THE U. S. GEOLOGICAL SURVEY STREAMGAGING NETWORK.
Arthur G. Scott
1986, Conference Paper
This paper summarizes the results from the first 3 years of a 5-year cost-effectiveness study of the U. S. Geological Survey streamgaging network. The objective of the study is to define and document the most cost-effective means of furnishing streamflow information. In the first step of this study, data uses...
Gas-film coefficients for the volatilization of ethylene dibromide from water
R. E. Rathbun, D.Y. Tal
1986, Environmental Science & Technology (20) 949-952
Gas-film coefficients for the volatilization of ethylene dibromide (EDB) and water were determined in the laboratory as a function of wind speed and temperature. The ratio of the coefficients was independent of wind speed and increased slightly with temperature. Use of this ratio with an environmentally determined gas-film coefficient for...
Adaptation of Selenastrum capricornutum (Chlorophyceae) to copper
J.S. Kuwabara, H.V. Leland
1986, Environmental Toxicology and Chemistry (5) 197-203
Selenastrum capricornutum Printz, growing in a chemically defined medium, was used as a model for studying adaptation of algae to a toxic metal (copper) ion. Cells exhibited lag‐phase adaptation to 0.8 μM total Cu (10−12 M free ion concentration) after 20 generations of Cu exposure. Selenastrum adapted to the same...
Movement and fate of detergents in groundwater: A field study
E.M. Thurman, L.B. Barber Jr., D. LeBlanc
1986, Journal of Contaminant Hydrology (1) 143-161
The major cations, anions, and detergents in a plume of contaminated groundwater at Otis Air Base on Cape Cod (Mass., U.S.A.) have moved approximately 3.5 km down gradient from the disposal beds. We hypothesize that the detergents form two distinct plumes, which consist of alkyl benzene sulfonates (ABS) detergents and...
Recalibration and predictive reliability of a solute-transport model of an irrigated stream-aquifer system
M. Person, Leonard F. Konikow
1986, Journal of Hydrology (87) 145-165
A solute-transport model of an irrigated stream-aquifer system was recalibrated because of discrepancies between prior predictions of ground-water salinity trends during 1971-1982 and the observed outcome in February 1982. The original model was calibrated with a 1-year record of data collected during 1971-1972 in an 18-km reach of the Arkansas...
Effect of ground-water recharge on configuration of the water table beneath sand dunes and on seepage in lakes in the sandhills of Nebraska, U.S.A.
T. C. Winter
1986, Journal of Hydrology (86) 221-237
Analysis of water-level fluctuations in about 30 observation wells and 5 lakes in the Crescent Lake National Wildlife Refuge in the sandhills of Nebraska indicates water-table configuration beneath sand dunes in this area varies considerably, depending on the configuration of the topography of the dunes. If the topography of an...
Use of detrended correspondence analysis to evaluate factors controlling spatial distribution of benthic insects
H.V. Leland, James L. Carter, Steven V. Fend
1986, Hydrobiologia (131) 113-123
Detrended correspondence analysis (DCA) was evaluated for its effectiveness in displaying factors controlling the spatial distribution of benthic insects in an oligotrophic stream where an experimental gradient (copper) that selectively affects population abundances was imposed. DCA proved to be highly sensitive to differences among samples and consistently provided ecologically meaningful...
Ground-water flow in low permeability environments
Christopher E. Neuzil
1986, Water Resources Research (22) 1163-1195
Certain geologic media are known to have small permeability; subsurface environments composed of these media and lacking well developed secondary permeability have groundwater flow sytems with many distinctive characteristics. Moreover, groundwater flow in these environments appears to influence the evolution of certain hydrologic, geologic, and geochemical systems, may affect the...
Geochemical investigations of selected Eastern United States watersheds affected by acid deposition
Owen P. Bricker
1986, Journal of the Geological Society (143) 621-626
The effects of acid deposition on surface waters in eastern United States watersheds having similar size, physiography, climate and land use are related to the composition of the underlying bedrock. Watersheds developed on greenstone, calcareous shale, sandstone, granite, and schist differ in their ability to neutralize acid deposition....
USGS NATIONAL MAPPING PROGRAM IN ALASKA--A STATUS REPORT.
Bruce Y. Mckenzie, Lowell E. Starr
1986, Conference Paper, Technical Papers of the American Society of Photogrammetry, Fall Technical Meeting
The U. S. Geological Survey has been involved in mapping in Alaska since the late 1800's. The initial mapping projects were principally in support of geologic or hydrologic studies. In the late 1940's, responsibility for Alaska mapping was assigned to the Geological Survey's Rocky Mountain Mapping Center and a comprehensive...
Aqueous dissolution, solubilities and thermodynamic stabilities of common aluminosilicate clay minerals: Kaolinite and smectites
Howard M. May, D.G. Klnniburgh, P.A. Helmke, Melanie L. Jackson
1986, Geochimica et Cosmochimica Acta (50) 1667-1677
Determinations of the aqueous solubilities of kaolinite at pH 4, and of five smectite minerals in suspensions set between pH 5 and 8, were undertaken with mineral suspensions adjusted to approach equilibrium from over- and undersaturation. After 1,237 days, Dry Branch, Georgia kaolinite...
Limitations in the use of commercial humic acids in water and soil research
Ronald L. Malcolm, P. MacCarthy
1986, Environmental Science & Technology (20) 904-911
Seven samples of commercial "humic acids", purchased from five different suppliers, were studied, and their characteristics were compared with humic and fulvic acids isolated from streams, soils, peat, leonardite, and a dopplerite sample. Cross-polarization and magic-angle spinning 13C NMR spectroscopy clearly shows pronounced differences between the commercial materials and all...
DEBRIS FLOWS AND HYPERCONCENTRATED STREAMFLOWS.
Gerald F. Wieczorek
1986, Conference Paper
Examination of recent debris-flow and hyperconcentrated-streamflow events in the western United States reveals (1) the topographic, geologic, hydrologic, and vegetative conditions that affect initiation of debris flows and (2) the wide ranging climatic conditions that can trigger debris flows. Recognition of these physiographic and climatic conditions has aided development of...
Determination of selected azaarenes in water by bonded-phase extraction and liquid chromatography
T.R. Steinheimer, M.G. Ondrus
1986, Analytical Chemistry (58) 1839-1844
A method for the rapid and simple quantitative determination of quinoline, isoquinoline, and five selected three-ring azaarenes in water has been developed. The azaarene fraction is separated from its carbon analogues on n-octadecyl packing material by edition with acidified water/acetonitrile. Concentration as great as 1000-fold is achieved readily. Instrumental analysis...
Geochemical evaluation of the geothermal resources in the San Marcos region, Guatemala
R.O. Fournier, B.B. Hanshaw
1986, Applied Geochemistry (1) 189-197
The chemical and isotopic compositions of hot springs in the San Marcos region of Guatemala are internally consistent with a hydrologic model in which a deep 240°C reservoir and one or more shallow 195–200°C reservoirs are present. Variations in hot-spring water...
Snow chemistry of the Cascade-Sierra Nevada Mountains
L.B. Laird, Howard E. Taylor, V. C. Kennedy
1986, Environmental Science & Technology (20) 275-290
This investigation assesses geographic variations in atmospheric deposition in Washington, Oregon, and California using snow cores from the Cascade-Sierra Nevada Mountains, collected from late February to mid-March 1983. A statistical analysis of the analytical and sampling precision was made. The snowpack in the higher Cascades and Sierra Nevada is not...
Geochemistry and aqueous chemistry of aluminum
J.D. Hem
1986, Kidney International S3-S7
No abstract available....
A comparison of two methods for determining copper partitioning in oxidized sediments
Samuel N. Luoma
1986, Marine Chemistry (20) 45-59
Model estimations of the proportion of Cu in oxidized sediments associated with extractable organic materials show some agreement with the proportion of Cu extracted from those sediments with ammonium hydroxide. Data were from 17 estuaries of widely differing sediment chemistry. The modelling and extraction methods agreed best where concentrations of...
