Peak flow responses to landscape disturbances caused by the cataclysmic 1980 eruption of Mount St. Helens, Washington
Jon J. Major, Linda E. Mark
2006, Geological Society of America Bulletin (118) 938-958
Years of discharge measurements that precede and follow the cataclysmic 1980 eruption of Mount St. Helens, Washington, provide an exceptional opportunity to examine the responses of peak flows to abrupt, widespread, devastating landscape disturbance. Multiple basins surrounding Mount St. Helens (300–1300 km2 drainage areas) were variously disturbed by: (1) a debris...
Effects of permafrost melting on CO2 and CH4 exchange of a poorly drained black spruce lowland
K.P. Wickland, Robert G. Striegl, J. C. Neff, T. Sachs
2006, Journal of Geophysical Research G: Biogeosciences (111)
[1] Permafrost melting is occurring in areas of the boreal forest region where large amounts of carbon (C) are stored in organic soils. We measured soil respiration, net CO2 flux, and net CH4 flux during May–September 2003 and March 2004 in a black spruce lowland in interior Alaska to...
Spatial patterns of fish communities along two estuarine gradients in southern Florida
D.P.J. Green, J.C. Trexler, J.J. Lorenz, C.C. McIvor, T. Philippi
2006, Hydrobiologia (569) 387-399
In tropical and subtropical estuaries, gradients of primary productivity and salinity are generally invoked to explain patterns in community structure and standing crops of fishes. We documented spatial and temporal patterns in fish community structure and standing crops along salinity and nutrient gradients in two subtropical drainages of Everglades National...
Using self-organizing maps to determine observation threshold limit predictions in highly variant data
C.A. Paganoni, K.C. Chang, M. B. Robblee
2006, Conference Paper, Proceedings of SPIE - The International Society for Optical Engineering
A significant data quality challenge for highly variant systems surrounds the limited ability to quantify operationally reasonable limits on the data elements being collected and provide reasonable threshold predictions. In many instances, the number of influences that drive a resulting value or operational range is too large to enable physical...
Late Quaternary landscape evolution in the Kunlun Mountains and Qaidam Basin, Northern Tibet: A framework for examining the links between glaciation, lake level changes and alluvial fan formation
L.A. Owen, R.C. Finkel, M. Haizhou, P.L. Barnard
2006, Quaternary International (154-155) 73-86
The Qaidam Basin in Northern Tibet is one of the largest hyper-arid intermontane basins on Earth. Alluvial fans, pediment surfaces, shorelines and a thick succession of sediments within the basin, coupled with moraines and associated landforms in the adjacent high mountain catchments of the Kunlun Mountains, record a complex history...
Measuring permanence of CO2 storage in saline formations: The Frio experiment
Susan D. Hovorka, Sally M. Benson, Christine Doughty, Barry M. Freifeild, Shinichi Sakurai, Thomas M. Daley, Yousif K. Kharaka, Mark H. Holtz, Robert C. Trautz, H. Seay Nance, Larry R. Myer, Kevin G. Knauss
2006, Environmental Geosciences (13) 105-121
If CO2 released from fossil fuel during energy production is returned to the subsurface, will it be retained for periods of time significant enough to benefit the atmosphere? Can trapping be assured in saline formations where there is no history of hydrocarbon accumulation? The Frio experiment in Texas was...
Use of borehole radar reflection logging to monitor steam-enhanced remediation in fractured limestone--Results of numerical modelling and a field experiment
C. Gregoire, P. K. Joesten, J.W. Lane Jr.
2006, Journal of Applied Geophysics (60) 41-54
Ground penetrating radar is an efficient geophysical method for the detection and location of fractures and fracture zones in electrically resistive rocks. In this study, the use of down-hole (borehole) radar reflection logs to monitor the injection of steam in fractured rocks was tested as part of a field-scale, steam-enhanced...
Increasing streamflow and baseflow in Mississippi River since the 1940 s: Effect of land use change
Y.-K. Zhang, K. E. Schilling
2006, Journal of Hydrology (324) 412-422
A trend of increasing streamflow has been observed in the Mississippi River (MR) basin since the 1940 s as a result of increased precipitation. Herein we show that increasing MR flow is mainly in its baseflow as a result of land use change and accompanying agricultural activities that occurred in...
Geochemistry of low-temperature springs northwest of Yellowstone caldera: Seeking the link between seismicity, deformation, and fluid flow
William C. Evans, Deborah Bergfeld, Matthias C. van Soest, Mark Huebner, John Fitzpatrick, Kinga M. Revesz
2006, Journal of Volcanology and Geothermal Research (154) 169-180
A comprehensive geochemical survey of springs outside the northwest margin of the Yellowstone caldera was undertaken in 2003 and 2004. This survey was designed to detect: (1) active leakage from a huge reservoir of CO2 gas recently postulated to extend from beneath the caldera into this area; and (2) lingering evidence...
Evaluation of the persistence of micropollutants through pure-oxygen activated sludge nitrification and denitrification
A.D. Levine, M. T. Meyer, G. Kish
2006, Water Environment Research (78) 2276-2285
The persistence of pharmaceuticals, hormones, and household and industrial chemicals through a pure-oxygen activated sludge, nitrification, denitrification wastewater treatment facility was evaluated. Of the 125 micropollutants that were tested in this study, 55 compounds were detected in the untreated wastewater, and 27 compounds were detected in the disinfected effluent. The...
One-way coupling of an atmospheric and a hydrologic model in Colorado
L.E. Hay, M.P. Clark, M. Pagowski, G.H. Leavesley, W.J. Gutowski
2006, Journal of Hydrometeorology (7) 569-589
This paper examines the accuracy of high-resolution nested mesoscale model simulations of surface climate. The nesting capabilities of the atmospheric fifth-generation Pennsylvania State University (PSU)-National Center for Atmospheric Research (NCAR) Mesoscale Model (MM5) were used to create high-resolution, 5-yr climate simulations (from 1 October 1994 through 30 September 1999), starting...
Phosphate oxygen isotope ratios as a tracer for sources and cycling of phosphate in North San Francisco Bay, California
K. McLaughlin, C. Kendall, S. R. Silva, M. Young, A. Paytan
2006, Journal of Geophysical Research G: Biogeosciences (111)
[1] A seasonal analysis assesing variations in the oxygen isotopic composition of dissolved inorganic phosphate (DIP) was conducted in the San Francisco Bay estuarine system, California. Isotopic fractionation of oxygen in DIP (exchange of oxygen between phosphate and environmental water) at surface water temperatures occurs only as...
Step wise, multiple objective calibration of a hydrologic model for a snowmelt dominated basin
L.E. Hay, G.H. Leavesley, M.P. Clark, S.L. Markstrom, Roland J. Viger, M. Umemoto
2006, Journal of the American Water Resources Association (42) 877-890
The ability to apply a hydrologic model to large numbers of basins for forecasting purposes requires a quick and effective calibration strategy. This paper presents a step wise, multiple objective, automated procedure for hydrologic model calibration. This procedure includes the sequential calibration of a model's simulation of solar radiation (SR),...
Effects of long-term water table drawdown on evapotranspiration and vegetation in an arid region phreatophyte community
D.J. Cooper, J.S. Sanderson, D.I. Stannard, D.P. Groeneveld
2006, Journal of Hydrology (325) 21-34
Evapotranspiration rates and the ground water component of evapotranspiration at a site in Colorado's San Luis Valley that is dominated by shrubby phreatophytes (greasewood and rabbitbrush) were compared before and after a water table drawdown. Evapotranspiration (ET) rates at the site were first measured in 1985-1987 (pre-drawdown) when the mean...
Effects of hurricanes Katrina and Rita on the chemistry of bottom sediments in Lake Pontchartrain, Louisiana, USA
P. C. Van Metre, A. J. Horowitz, B.J. Mahler, W.T. Foreman, C. C. Fuller, M.R. Burkhardt, K. A. Elrick, E. T. Furlong, S. C. Skrobialowski, J.J. Smith, J.T. Wilson, S.D. Zaugg
2006, Environmental Science & Technology (40) 6894-6902
The effects of Hurricanes Katrina and Rita and the subsequent unwatering of New Orleans, Louisiana, on the sediment chemistry of Lake Pontchartrain were evaluated by chemical analysis of samples of street mud and suspended and bottom sediments. The highest concentrations of urban-related elements and compounds (e.g., Pb,...
A 16-year record of eolian dust in Southern Nevada and California, USA: Controls on dust generation and accumulation
M.C. Reheis
2006, Journal of Arid Environments (67) 487-520
An ongoing project monitors modern dust accumulation in the arid southwestern United States to (1) determine the rate and composition of dust inputs to soils and (2) relate dust accumulation to weather patterns to help predict the effects of climate change on dust production and accumulation. The 16-year records of...
Tracer test with As(V) under variable redox conditions controlling arsenic transport in the presence of elevated ferrous iron concentrations
R. Hohn, M. Isenbeck-Schroter, D.B. Kent, J.A. Davis, R. Jakobsen, S. Jann, V. Niedan, C. Scholz, S. Stadler, A. Tretner
2006, Journal of Contaminant Hydrology (88) 36-54
To study transport and reactions of arsenic under field conditions, a small-scale tracer test was performed in an anoxic, iron-reducing zone of a sandy aquifer at the USGS research site on Cape Cod, Massachusetts, USA. For four weeks, a stream of groundwater with added As(V) (6.7 μM) and bromide...
Environmental and geochemical record of human-induced changes in C storage during the last millennium in a temperate wetland (Las Tablas de Daimiel National Park, central Spain)
F. Dominguez-Castro, J.I. Santisteban, R. Mediavilla, W.E. Dean, E. Lopez-Pamo, M. J. Gil-Garcia, M. B. Ruiz-Zapata
2006, Conference Paper, Tellus, Series B: Chemical and Physical Meteorology
Las Tablas de Daimiel National Park has experienced many hydrological and ecological modifications through out its history, both of natural as well as anthropogenic origin, which have affected its carbon storage capacity and carbon fluxes. The study of those variations has been carried out by the analysis of its sedimentary...
Development of the performance confirmation program at YUCCA mountain, nevada
G.D. LeCain, D. Barr, D. Weaver, R. Snell, S.W. Goodin, F.D. Hansen
2006, Conference Paper, Proceedings of the 11th International High Level Radioactive Waste Management Conference, IHLRWM
The Yucca Mountain Performance Confirmation program consists of tests, monitoring activities, experiments, and analyses to evaluate the adequacy of assumptions, data, and analyses that form the basis of the conceptual and numerical models of flow and transport associated with a proposed radioactive waste repository at Yucca Mountain, Nevada. The Performance...
Use of borehole radar tomography to monitor steam injection in fractured limestone
C. Gregoire, P. K. Joesten
2006, Near Surface Geophysics (4) 355-365
Borehole radar tomography was used as part of a pilot study to monitor steam‐enhanced remediation of a fractured limestone contaminated with volatile organic compounds at the former Loring Air Force Base, Maine, USA. Radar tomography data were collected using 100‐MHz electric‐dipole antennae before and during steam injection to evaluate whether...
Aspects of the biology of Salicornia bigelovii torr. In relation to a proposed restoration of a wind-tidal flat system on the South Texas, USA Coast
C.P. Onuf
2006, Wetlands (26) 649-666
Wind-tidal flats are the dominant coastal wetland type in southern Texas USA. Succulent vascular plants are colonizing the flats in some locations, often where past dredge disposal along navigation channels and other activities have interrupted natural water communication between hypersaline bays and large areas of wind-tidal flats. The objective of...
Denitrification in nitrate-rich streams: Application of N2:Ar and 15N-tracer methods in intact cores
Lesley K. Smith, M.A. Voytek, J.K. Böhlke, J. W. Harvey
2006, Ecological Applications (16) 2191-2207
Rates of benthic denitrification were measured using two techniques, membrane inlet mass spectrometry (MIMS) and isotope ratio mass spectrometry (IRMS), applied to sediment cores from two NO3−‐rich streams draining agricultural land in the upper Mississippi River Basin. Denitrification was estimated simultaneously from measurements of N2:Ar (MIMS) and 15N[N2]...
Survey of organic wastewater contaminants in biosolids destined for land application
C.A. Kinney, E. T. Furlong, S.D. Zaugg, M.R. Burkhardt, S.L. Werner, J.D. Cahill, G.R. Jorgensen
2006, Environmental Science & Technology (40) 7207-7215
In this study, the presence, composition, and concentrations of organic wastewater contaminants (OWCs) were determined in solid materials produced during wastewater treatment. This study was undertaken to evaluate the potential of these solids, collectively referred to as biosolids, as a source of OWCs to soil and water...
Occurrence and fate of organic contaminants during onsite wastewater treatment
K.E. Conn, L. B. Barber, G.K. Brown, R.L. Siegrist
2006, Environmental Science & Technology (40) 7358-7366
Onsite wastewater treatment systems serve approximately 25% of the U.S. population. However, little is known regarding the occurrence and fate of organic wastewater contaminants (OWCs), including endocrine disrupting compounds, during onsite treatment. A range of OWCs including surfactant metabolites, steroids, stimulants, metal-chelating agents, disinfectants, antimicrobial agents, and...
Factors influencing soil invertebrate communities in riparian grasslands of the central platte river floodplain
C.A. Davis, J. E. Austin, D. A. Buhl
2006, Wetlands (26) 438-454
In the Platte River Valley of central Nebraska, USA, riparian grasslands (also known as wet meadows) have been severely impacted by a reduction in river flows, causing lower ground-water levels and altered seasonal hydroperiods. The potential impacts of these hydrologic changes, as well as the environmental factors that influence wet...
