Publications
Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).
Filter Total Items: 3746
Soil science and geology: Connects, disconnects and new opportunities in geoscience education
Despite historical linkages, the fields of geology and soil science have developed along largely divergent paths in the United States during much of the mid- to late- twentieth century. The shift in recent decades within both disciplines to greater emphasis on environmental quality issues and a systems approach has created new opportunities for collaboration and cross-training. Because of the impo
Authors
E. R. Landa
Relative effect of temperature and pH on diel cycling of dissolved trace elements in Prickly Pear Creek, Montana
Diel (24 hr) cycles in dissolved metal and As concentrations have been documented in many northern Rocky Mountain streams in the U.S.A. The cause(s) of the cycles are unknown, although temperature- and pH-dependent sorption reactions have been cited as likely causes. A light/dark experiment was conducted to isolate temperature and pH as variables affecting diel metal cycles in Prickly Pear Creek,
Authors
Clain A. Jones, D. A. Nimick, R. Blaine McCleskey
Using dual-bacterial denitrification to improve δ15N determinations of nitrates containing mass-independent 17O
The bacterial denitrification method for isotopic analysis of nitrate using N2O generated from Pseudomonas aureofaciens may overestimate δ15N values by as much as 1–2‰ for samples containing atmospheric nitrate because of mass-independent 17O variations in such samples. By analyzing such samples for δ15N and δ18O using the denitrifier Pseudomonas chlororaphis, one obtains nearly correct δ15N value
Authors
Tyler B. Coplen, John K. Böhlke, Karen L. Casciotti
Conservative and reactive solute transport in constructed wetlands
The transport of bromide, a conservative tracer, and rhodamine WT (RWT), a photodegrading tracer, was evaluated in three wastewater‐dependent wetlands near Phoenix, Arizona, using a solute transport model with transient storage. Coupled sodium bromide and RWT tracer tests were performed to establish conservative transport and reactive parameters in constructed wetlands with water losses ranging fr
Authors
Steffanie H. Keefe, Larry B. Barber, Robert L. Runkel, Joseph N. Ryan, Diane M. McKnight, Roland D. Wass
Uptake pathway for Ag bioaccumulation in three benthic invertebrates exposed to contaminated sediments
We exposed 3 benthic invertebrates, the clam Macoma balthica, the polychaete Neanthes arenaceodentataand the amphipod Leptocheirus plumulosus, to Ag-contaminated sediments to evaluate the relative importance of various uptake routes (sediments, porewater or overlying water, and supplementary food) for Ag bioaccumulation. Silver bioaccumulation was evaluated at 4 levels of sediment Ag (0.1, 0,3, 1,
Authors
H. Yoo, J.-S. Lee, B.-G. Lee, I.T. Lee, C.E. Schlekat, C.-H. Koh, S. N. Luoma
Reach-scale isotope tracer experiment to quantify denitrification and related processes in a nitrate-rich stream, midcontinent United States
We conducted an in-stream tracer experiment with Br and 15N-enriched NO3- to determine the rates of denitrification and related processes in a gaining NO3- -rich stream in an agricultural watershed in the upper Mississippi basin in September 2001. We determined reach-averaged rates of N fluxes and reactions from isotopic analyses of NO3-, NO2-, N2, and suspended particulate N in conjunction with o
Authors
J.K. Böhlke, J. W. Harvey, M.A. Voytek
Lateral mixing in the Mississippi River below the confluence with the Ohio River
Lateral dispersion coefficients for two dispersants were determined for three sections of the Mississippi River below the confluence with the Ohio River. The dispersants were the specific conductance and an industrial organic compound (trimethyltriazinetrione). Three models based on the stream tube concept were used, and lateral dispersion coefficients computed from these models were comparable. C
Authors
R. E. Rathbun, C.E. Rostad
Tritium hydrology of the Mississippi River basin
In the early 1960s, the US Geological Survey began routinely analysing river water samples for tritium concentrations at locations within the Mississippi River basin. The sites included the main stem of the Mississippi River (at Luling Ferry, Louisiana), and three of its major tributaries, the Ohio River (at Markland Dam, Kentucky), the upper Missouri River (at Nebraska City, Nebraska) and the Ark
Authors
R. L. Michel
Contamination of groundwater under cultivated fields in an arid environment, central Arava Valley, Israel
The purpose of this study is to obtain a better understanding of groundwater contamination processes in an arid environment (precipitation of 50 mm/year) due to cultivation. Additional aims were to study the fate of N, K, and other ions along the whole hydrological system including the soil and vadose zone, and to compare groundwater in its natural state with contaminated groundwater (through the
Authors
O. Oren, Y. Yechieli, J.K. Böhlke, A. Dody
Assessing the resolution-dependent utility of tomograms for geostatistics
Geophysical tomograms are used increasingly as auxiliary data for geostatistical modeling of aquifer and reservoir properties. The correlation between tomographic estimates and hydrogeologic properties is commonly based on laboratory measurements, co-located measurements at boreholes, or petrophysical models. The inferred correlation is assumed uniform throughout the interwell region; however, tom
Authors
F. D. Day-Lewis, J.W. Lane
SWICA-2 M3: Second conference on salt water intrusion in coastal aquifers: Monitoring, modeling, and management
No abstract available
Authors
L.E. Marin, C.I. Voss
Inorganic N and P dynamics of Antarctic glacial meltwater streams as controlled by hyporheic exchange and benthic autotrophic communities
The McMurdo Dry Valleys of South Victoria Land, Antarctica, contain numerous glacial meltwater streams that drain into lakes on the valley floors. Many of the streams have abundant perennial mats of filamentous cyanobacteria. The algal mats grow during streamflow in the austral summer and are in a dormant freeze-dried state during the rest of the year. NO3 and soluble reactive P (SRP) concentratio
Authors
Diane M. McKnight, R.L. Runkel, C. M. Tate, J.H. Duff, D.L. Moorhead