Potential for 4-n-nonylphenol biodegradation in stream sediments
P. M. Bradley, L. B. Barber, D.W. Kolpin, P.B. McMahon, F. H. Chapelle
2008, Environmental Toxicology and Chemistry (27) 260-265
The potential for in situ biodegradation of 4-nonylphenol (4-NP) was investigated in three hydrologically distinct streams impacted by wastewater treatment plants (WWTPs) in the United States. Microcosms were prepared with sediments from each site and amended with [U-ring-14C]4-n-nonylphenol (4-n-NP) as a model test substrate. Microcosms prepared with sediment collected upstream...
Peat porewater chloride concentration profiles in the Everglades during wet/dry cycles from January 1996 to June 1998: Field measurements and theoretical analysis
M.M. Reddy, M.B. Reddy, K.L. Kipp, A. Burman, Peter Schuster, P.S. Rawlik Jr.
2008, Hydrological Processes (22) 1713-1724
Water quality is a key aspect of the Everglades Restoration Project, the largest water reclamation and ecosystem management project proposed in the United States. Movement of nutrients and contaminants to and from Everglades peat porewater could have important consequences for Everglades water quality and ecosystem restoration activities. In a study...
Chromium, chromium isotopes and selected trace elements, western Mojave Desert, USA
J. A. Izbicki, J.W. Ball, T.D. Bullen, S. J. Sutley
2008, Applied Geochemistry (23) 1325-1352
Chromium(VI) concentrations in excess of the California Maximum Contaminant Level (MCL) of 50 μg/L occur naturally in alkaline, oxic ground-water in alluvial aquifers in the western Mojave Desert, southern California. The highest concentrations were measured in aquifers eroded from mafic rock, but Cr(VI)...
Changes in the character of DOC in streams during storms in two Midwestern watersheds with contrasting land uses
P. Vidon, L.E. Wagner, E. Soyeux
2008, Biogeochemistry (88) 257-270
Dissolved organic carbon (DOC) dynamics in streams is important, yet few studies focus on DOC dynamics in Midwestern streams during storms. In this study, stream DOC dynamics during storms in two Midwestern watersheds with contrasting land uses, the change in character of stream DOC during storms, and the usability of...
Investigation and hazard assessment of the 2003 and 2007 Staircase Falls rock falls, Yosemite National Park, California, USA
G. F. Wieczorek, Gregory M. Stock, P. Reichenbach, J.B. Snyder, J. W. Borchers, J. W. Godt
2008, Natural Hazards and Earth System Sciences (8) 421-432
Since 1857 more than 600 rock falls, rock slides, debris slides, and debris flows have been documented in Yosemite National Park, with rock falls in Yosemite Valley representing the majority of the events. On 26 December 2003, a rock fall originating from west of Glacier Point sent approximately 200 m...
Susceptibility to enhanced chemical migration from depression-focused preferential flow, High Plains aquifer
Jason J. Gurdak, Michelle Ann Walvoord, Peter B. McMahon
2008, Vadose Zone Journal (7) 1172-1184
Aquifer susceptibility to contamination is controlled in part by the inherent hydrogeologic properties of the vadose zone, which includes preferential-flow pathways. The purpose of this study was to investigate the importance of seasonal ponding near leaky irrigation wells as a mechanism for depression-focused preferential flow and enhanced chemical migration through...
Soil slip/debris flow localized by site attributes and wind-driven rain in the San Francisco Bay region storm of January 1982
R.J. Pike, S. Sobieszczyk
2008, Geomorphology (94) 290-313
GIS analysis at 30-m resolution reveals that effectiveness of slope-destabilizing processes in the San Francisco Bay area varies with compass direction. Nearly half the soil slip/debris flows mapped after the catastrophic rainstorm of 3-5 January 1982 occurred on slopes that face S to WSW, whereas fewer than one-quarter have a...
A multi-residue method for the analysis of pesticides and pesticide degradates in water using HLB solid-phase extraction and gas chromatography-ion trap mass spectrometry
M.L. Hladik, K.L. Smalling, K.M. Kuivila
2008, Bulletin of Environmental Contamination and Toxicology (80) 139-144
A method was developed for the analysis of over 60 pesticides and degradates in water by HLB solid-phase extraction and gas-chromatography/mass spectrometry. Method recoveries and detection limits were determined using two surface waters with different dissolved organic carbon (DOC) concentrations. In the lower DOC water, recoveries and detection limits...
Determination of dominant biogeochemical processes in a contaminated aquifer-wetland system using multivariate statistical analysis
S. E. Baez-Cazull, J.T. McGuire, I.M. Cozzarelli, M.A. Voytek
2008, Journal of Environmental Quality (37) 30-46
Determining the processes governing aqueous biogeochemistry in a wetland hydrologically linked to an underlying contaminated aquifer is challenging due to the complex exchange between the systems and their distinct responses to changes in precipitation, recharge, and biological activities. To evaluate temporal and spatial processes in the wetland-aquifer system, water samples...
Suspended sediment transport in the freshwater reach of the Hudson river estuary in eastern New York
G. R. Wall, E.A. Nystrom, S. Litten
2008, Estuaries and Coasts (31) 542-553
Deposition of Hudson River sediment into New York Harbor interferes with navigation lanes and requires continuous dredging. Sediment dynamics at the Hudson estuary turbidity maximum (ETM) have received considerable study, but delivery of sediment to the ETM through the freshwater reach of the estuary has received relatively little attention and...
Evaporite-karst problems and studies in the USA
K.S. Johnson
2008, Conference Paper, Environmental Geology
Evaporites, including rock salt (halite) and gypsum (or anhydrite), are the most soluble among common rocks; they dissolve readily to form the same types of karst features that commonly are found in limestones and dolomites. Evaporites are present in 32 of the 48 contiguous states in USA, and they underlie...
Permeability of continental crust influenced by internal and external forcing
S.A. Rojstaczer, S. E. Ingebritsen, D.O. Hayba
2008, Geofluids (8) 128-139
The permeability of continental crust is so highly variable that it is often considered to defy systematic characterization. However, despite this variability, some order has been gleaned from globally compiled data. What accounts for the apparent coherence of mean permeability in the continental crust (and permeability–depth relations) on a very...
Effects of ionic strength, temperature, and pH on degradation of selected antibiotics
K.A. Loftin, C.D. Adams, M. T. Meyer, R. Surampalli
2008, Journal of Environmental Quality (37) 378-386
Aqueous degradation rates, which include hydrolysis and epimerization, for chlortetracycline (CTC), oxytetracycline (OTC), tetracycline (TET), lincomycin (LNC), sulfachlorpyridazine (SCP), sulfadimethoxine (SDM), sulfathiazole (STZ), trimethoprim (TRM), and tylosin A (TYL) were studied as a function of ionic strength (0.0015, 0.050, or 0.084 mg/L as Na2HPO4), temperature (7, 22, and 35°C), and...
Mid-infrared diffuse reflectance spectroscopic examination of charred pine wood, bark, cellulose, and lignin: Implications for the quantitative determination of charcoal in soils
J. B. Reeves III, G.W. McCarty, D.W. Rutherford, R.L. Wershaw
2008, Applied Spectroscopy (62) 182-189
Fires in terrestrial ecosystems produce large amounts of charcoal that persist in the environment and represent a substantial pool of sequestered carbon in soil. The objective of this research was to investigate the effect of charring on mid-infrared spectra of materials likely to be present in forest...
Reply to comment by J. Szilagyi on "Comparison of 15 evaporation methods applied to a small mountain lake in the northeastern USA" [J. Hydrol. 340 (3-4) (2007) 149-166]
D.O. Rosenberry, T. C. Winter, D.C. Buso, G.E. Likens
2008, Journal of Hydrology (348) 566-567
[No abstract available]...
Mathematical models frame environmental dispute [Review of the article Useless arithmetic: Ten points to ponder when using mathematical models in environmental decision making]
Berton Lee Lamb, Nina Burkardt
2008, Public Administration Review (68) 55-60
When Linda Pilkey- Jarvis and Orrin Pilkey state in their article, "Useless Arithmetic," that "mathematical models are simplified, generalized representations of a process or system," they probably do not mean to imply that these models are simple. Rather, the models are simpler than nature and that is the heart of...
Application of MODFLOW’s farm process to California’s Central Valley
Claudia C. Faunt, Randall T. Hanson, Wolfgang Schmid, Kenneth Belitz
2008, Conference Paper, California Central Valley Groundwater Modeling Workshop, Proceedings
Historically, California’s Central Valley has been one of the most productive agricultural regions in the world. The Central Valley also is rapidly becoming an important area for California’s expanding urban population. During 1980–2007, the population nearly doubled in the Central Valley, increasing the competition for water. Because of the importance...
Differences in evaporation between a floating pan and class a pan on land
J.R. Masoner, D.I. Stannard, S. C. Christenson
2008, Journal of the American Water Resources Association (44) 552-561
Research was conducted to develop a method for obtaining floating pan evaporation rates in a small (less than 10,000 m2) wetland, lagoon, or pond. Floating pan and land pan evaporation data were collected from March 1 to August 31, 2005, at a small natural wetland located in the alluvium of the...
Fiber‐optic distributed temperature sensing: A new tool for assessment and monitoring of hydrologic processes
John W. Lane Jr., Frederick D. Day-Lewis, Carole D. Johnson, Cian B. Dawson, David L. Nelms, Cheryl A. Eddy-Miller, Jerrod D. Wheeler, Charles F. Harvey, Hanan N. Karam
2008, Conference Paper, Symposium on the Application of Geophysics to Engineering and Environmental Problems 2008
Fiber‐optic distributed temperature sensing (FO DTS) is an emerging technology for characterizing and monitoring a wide range of important earth processes. FO DTS utilizes laser light to measure temperature along the entire length of standard telecommunications optical fibers. The technology can measure temperature every meter over FO cables up to...
Modeling soil moisture processes and recharge under a melting snowpack
A. L. Flint, L. E. Flint, M. D. Dettinger
2008, Conference Paper, Vadose Zone Journal
Recharge into granitic bedrock under a melting snowpack is being investigated as part of a study designed to understand hydrologic processes involving snow at Yosemite National Park in the Sierra Nevada Mountains of California. Snowpack measurements, accompanied by water content and matric potential measurements of the soil under the snowpack,...
Attribution of declining Western U.S. Snowpack to human effects
D.W. Pierce, T.P. Barnett, H.G. Hidalgo, T. Das, Celine Bonfils, B.D. Santer, G. Bala, M. D. Dettinger, D.R. Cayan, A. Mirin, A.W. Wood, T. Nozawa
2008, Journal of Climate (21) 6425-6444
Observations show snowpack has declined across much of the western United States over the period 1950-99. This reduction has important social and economic implications, as water retained in the snowpack from winter storms forms an important part of the hydrological cycle and water supply in the region. A formal model-based...
InSAR detects possible thaw settlement in the Alaskan Arctic Coastal Plain
Russell P. Rykhus, Zhong Lu
2008, Canadian Journal of Remote Sensing (34) 100-112
Satellite interferometric synthetic aperture radar (InSAR) has proven to be an effective tool for monitoring surface deformation from volcanoes, earthquakes, landslides, and groundwater withdrawal. This paper seeks to expand the list of applications of InSAR data to include monitoring subsidence possibly associated with thaw settlement over the Alaskan Arctic Coastal...
CO2‐induced suppression of transpiration cannot explain increasing runoff
Thomas G. Huntington
2008, Hydrological Processes (22) 311-314
No abstract available....
Questa baseline and pre-mining ground-water quality investigation. 17. Geomorphology of the Red River Valley, Taos County, New Mexico, and influence on ground-water flow in the shallow alluvial aquifer
Kirk R. Vincent
2008, Scientific Investigations Report 2006-5156
In April 2001, the U.S. Geological Survey (USGS) and the New Mexico Environment Department (NMED) began a cooperative study to infer the pre-mining ground-water chemistry at the Molycorp molybdenum mine site in the Red River Valley of north-central New Mexico. This report is one in a series of reports that...
Effects of urbanization on stream ecosystems in the Willamette River basin and surrounding area, Oregon and Washington
Ian R. Waite, Steven Sobieszczyk, Kurt D. Carpenter, Andrew J. Arnsberg, Henry M. Johnson, Curt A. Hughes, Michael J. Sarantou, Frank A. Rinella
2008, Scientific Investigations Report 2006-5101-D
This report describes the effects of urbanization on physical, chemical, and biological characteristics of stream ecosystems in 28 watersheds along a gradient of urbanization in the Willamette River basin and surrounding area, Oregon and Washington, from 2003 through 2005. The study that generated the report is one of several urban-effects...
