Chloroethene biodegradation in sediments at 4°C
P. M. Bradley, S. Richmond, F. H. Chapelle
2005, Applied and Environmental Microbiology (71) 6414-6417
Microbial reductive dechlorination of [1,2-14C]trichloroethene to [14C]cis-dichloroethene and [14C]vinyl chloride was observed at 4°C in anoxic microcosms prepared with cold temperature-adapted aquifer and river sediments from Alaska. Microbial anaerobic oxidation of [1,2-14C]cis-dichloroethene and [1,2-14C]vinyl chloride to 14CO2 also was observed under these conditions. ...
Extraordinary flood response of a small urban watershed to short-duration convective rainfall
J. A. Smith, A.J. Miller, M.L. Baeck, P.A. Nelson, G. T. Fisher, K.L. Meierdiercks
2005, Journal of Hydrometeorology (6) 599-617
The 9.1 km2 Moores Run watershed in Baltimore, Maryland, experiences floods with unit discharge peaks exceeding 1 m3 s-1 km-2 12 times yr-1, on average. Few, if any, drainage basins in the continental United States have a higher frequency. A thunderstorm system on 13 June 2003 produced the record flood...
Channelization and floodplain forests: Impacts of accelerated sedimentation and valley plug formation on floodplain forests of the Middle Fork Forked Deer River, Tennessee, USA
S.N. Oswalt, S.L. King
2005, Forest Ecology and Management (215) 69-83
We evaluated the severe degradation of floodplain habitats resulting from channelization and concomitant excessive coarse sedimentation on the Middle Fork Forked Deer River in west Tennessee from 2000 to 2003. Land use practices have resulted in excessive sediment in the tributaries and river system eventually resulting in sand deposition on...
Comparison of Bacteroides-Prevotella 16S rRNA genetic markers for fecal samples from different animal species
L.R. Fogarty, M.A. Voytek
2005, Applied and Environmental Microbiology (71) 5999-6007
To effectively manage surface and ground waters it is necessary to improve our ability to detect and identify sources of fecal contamination. We evaluated the use of the anaerobic bacterial group Bacteroides-Prevotella as a potential fecal indicator. Terminal restriction length polymorphism (T-RFLP) of the 16S rRNA genes from this group...
Effects of suburban development on runoff generation in the Croton River basin, New York, USA
Douglas A. Burns, T. Vitvar, J. McDonnell, J. Hassett, J. Duncan, Carol Kendall
2005, Journal of Hydrology (311) 266-281
The effects of impervious area, septic leach-field effluent, and a riparian wetland on runoff generation were studied in three small (0.38–0.56 km2) headwater catchments that represent a range of suburban development (high density residential, medium density residential, and undeveloped) within the Croton River basin, 70 km north of New York City. Precipitation, stream...
Evidence and implications of recent climate change in Northern Alaska and other Arctic regions
L. D. Hinzman, N.D. Bettez, W.R. Bolton, F.S. Chapin, M.B. Dyurgerov, C.L. Fastie, B. Griffith, R.D. Hollister, Allen Hope, H.P. Huntington, A.M. Jensen, G.J. Jia, T. Jorgenson, D.L. Kane, D.R. Klein, G. Kofinas, A.H. Lynch, A.H. Lloyd, A. D. McGuire, Frederick E. Nelson, W.C. Oechel, T.E. Osterkamp, C.H. Racine, V.E. Romanovsky, R. S. Stone, D.A. Stow, M. Sturm, C.E. Tweedie, G.L. Vourlitis, M.D. Walker, D.A. Walker, P.J. Webber, J.M. Welker, K.S. Winker, K. Yoshikawa
2005, Climatic Change (72) 251-298
The Arctic climate is changing. Permafrost is warming, hydrological processes are changing and biological and social systems are also evolving in response to these changing conditions. Knowing how the structure and function of arctic terrestrial ecosystems are responding to recent and persistent climate change is paramount to understanding the future...
Impact of land use and land cover change on groundwater recharge and quality in the southwestern US
Bridget R. Scanlon, Robert C. Reedy, David A. Stonestrom, David E. Prudic, Kevin F. Dennehy
2005, Global Change Biology (11) 1577-1593
Humans have exerted large‐scale changes on the terrestrial biosphere, primarily through agriculture; however, the impacts of such changes on the hydrologic cycle are poorly understood. The purpose of this study was to test the hypothesis that the conversion of natural rangeland ecosystems to agricultural ecosystems impacts the subsurface portion of...
Percolation and transport in a sandy soil under a natural hydraulic gradient
Christopher T. Green, David A. Stonestrom, Barbara A. Bekins, Katherine C. Akstin, Marjorie S. Schulz
2005, Water Resources Research (41)
Unsaturated flow and transport under a natural hydraulic gradient in a Mediterranean climate were investigated with a field tracer experiment combined with laboratory analyses and numerical modeling. Bromide was applied to the surface of a sandy soil during the dry season. During the subsequent rainy season, repeated sediment sampling tracked...
Effects of stream flow intermittency on riparian vegetation of a semiarid region river (San Pedro River, Arizona)
J.C. Stromberg, K.J. Bagstad, J.M. Leenhouts, S.J. Lite, E. Makings
2005, River Research and Applications (21) 925-938
The San Pedro River in the southwestern United States retains a natural flood regime and has several reaches with perennial stream flow and shallow ground water. However, much of the river flows intermittently. Urbanization-linked declines in regional ground-water levels have raised concerns over the future status of the riverine ecosystem...
Combined use of 15N and 18O of nitrate and 11B to evaluate nitrate contamination in groundwater
R. L. Seiler
2005, Applied Geochemistry (20) 1626-1636
Isotopic composition of NO3 (??15NNO3 and ??18ONO3) and B (??11B) were used to evaluate NO3 contamination and identify geochemical processes occurring in a hydrologically complex Basin and Range valley in northern Nevada with multiple potential sources of NO3. Combined use of these isotopes may be a useful tool in identifying...
Use of relational databases to evaluate regional petroleum accumulation, groundwater flow, and CO2 sequestration in Kansas
T.R. Carr, D. F. Merriam, J.D. Bartley
2005, American Association of Petroleum Geologists Bulletin (89) 1607-1627
Large-scale relational databases and geographic information system tools are used to integrate temperature, pressure, and water geo-chemistry data from numerous wells to better understand regional-scale geothermal and hydrogeological regimes of the lower Paleozoic aquifer systems in the mid-continent and to evaluate their potential for geologic CO2 sequestration. The lower Paleozoic...
Nitrogen and carbon flow from rock to water: Regulation through soil biogeochemical processes, Mokelumne River watershed, California, and Grand Valley, Colorado
J.M. Holloway, R. L. Smith
2005, Journal of Geophysical Research F: Earth Surface (110)
Soil denitrification is an ecologically important nitrogen removal mechanism that releases to the atmosphere the greenhouse gas N2O, an intermediate product from the reduction of NO3- to N 2. In this study we evaluate the relationship between soil carbon and denitrification potential in watersheds with bedrock acting as a nonpoint...
Part 2: A field study of enhanced remediation of Toluene in the vadose zone using a nutrient solution
J.A. Tindall, E.P. Weeks, M. Friedel
2005, Water, Air, & Soil Pollution (168) 359-389
The objective of this study was to test the effectiveness of a nitrate-rich nutrient solution and hydrogen peroxide (H2O2) to enhance in-situ microbial remediation of toluene in the unsaturated zone. Three sand-filled plots were tested in three phases (each phase lasting approximately 2 weeks). During the control phase, toluene...
Reconstructing a mid-Cretaceous landscape from paleosols in western Canada
David F. Ufnar, Luis A. Gonzalez, Greg A. Ludvigson, Richard L. Brenner, B.J. Witzke, D. Leckie
2005, Journal of Sedimentary Research (75) 984-996
The Albian Stage of the mid-Cretaceous was a time of equable climate conditions with high sea levels and broad shallow epeiric seas that may have had a moderating affect on continental climates. A Late Albian landscape surface that developed during a regression and subsequent sea-level rise in the Western Canada...
Assessing water source and channel type as factors affecting benthic macroinvertebrate and periphyton assemblages in the highly urbanized Santa Ana River Basin, California
Carmen A. Burton, Larry R. Brown, Kenneth Belitz
2005, American Fisheries Society Symposium (2005) 239-262
The Santa Ana River basin is the largest stream system in Southern California and includes a densely populated coastal area. Extensive urbanization has altered the geomorphology and hydrology of the streams, adversely affecting aquatic communities. We studied macroinvertebrate and periphyton assemblages in relation to two categorical features of the highly...
Delineating copper accumulation pathways for the freshwater bivalve Corbicula using stable copper isotopes
M.-N. Croteau, S. N. Luoma
2005, Environmental Toxicology and Chemistry (24) 2871-2878
Delineation of metal uptake routes in aquatic invertebrates is critical for characterizing bioaccumulation dynamics and assessing risks associated with metal exposure. Here we demonstrate that Cu stable isotopic ratios can be manipulated in both exposure media and algae to determine the efflux rate constant (ke) and...
Palaeohydrology of the Southwest Yukon Territory, Canada, based on multiproxy analyses of lake sediment cores from a depth transect
L. Anderson, M.B. Abbott, B. P. Finney, M. E. Edwards
2005, Holocene (15) 1172-1183
Lake-level variations at Marcella Lake, a small, hydrologically closed lake in the southwestern Yukon Territory, document changes in effective moisture since the early Holocene. Former water levels, driven by regional palaeohydrology, were reconstructed by multiproxy analyses of sediment cores from four sites spanning shallow to deep water. Marcella Lake today...
Part 1: Vadose-zone column studies of toluene (enhanced bioremediation) in a shallow unconfined aquifer
J.A. Tindall, M.J. Friedel, R.J. Szmajter, S.M. Cuffin
2005, Water, Air, & Soil Pollution (168) 325-357
The objectives of the laboratory study described in this paper were (1) to determine the effectiveness of four nutrient solutions and a control in stimulating the microbial degradation of toluene in the unsaturated zone as an alternative to bioremediation methodologies such as air sparging, in situ vitrification, or others...
Steam injection pilot study in a contaminated fractured limestone (Maine, USA): Modeling and analysis of borehole radar reflection data
C. Gregoire, J.W. Lane Jr., P. K. Joesten
2005, Conference Paper, Proceedings of the 3rd International Workshop on Advanced Ground Penetrating Radar, IWAGPR 2005
Steam-enhanced remediation (SER) has been successfully used to remove DNAPL and LNAPL contaminants in porous media. Between August and November 2002, SER was tested in fractured limestone at the former Loring Air Force Base, in Maine, USA. During the SER investigation, the U.S. Geological Survey conducted a series of borehole...
Comparison of a novel passive sampler to standard water-column sampling for organic contaminants associated with wastewater effluents entering a New Jersey stream
D.A. Alvarez, P. E. Stackelberg, J. D. Petty, J.N. Huckins, E. T. Furlong, S.D. Zaugg, M. T. Meyer
2005, Chemosphere (61) 610-622
Four water samples collected using standard depth and width water-column sampling methodology were compared to an innovative passive, in situ, sampler (the polar organic chemical integrative sampler or POCIS) for the detection of 96 organic wastewater-related contaminants (OWCs) in a stream that receives agricultural, municipal, and industrial wastewaters. Thirty-two OWCs...
An ostracode based paleolimnologic and paleohydrologic history of Death Valley: 200 to 0 ka
R. M. Forester, T.K. Lowenstein, R. J. Spencer
2005, Geological Society of America Bulletin (117) 1379-1386
Death Valley, a complex tectonic and hydrologic basin, was cored from its lowest surface elevation to a depth of 186 m. The sediments range from bedded primary halite to black muds. Continental ostracodes found in the black muds indicate that those sediments were deposited in a variety of hydrologic settings...
Sensitivity analysis of conservative and reactive stream transient storage models applied to field data from multiple-reach experiments
M.N. Gooseff, K.E. Bencala, D.T. Scott, R.L. Runkel, Diane M. McKnight
2005, Advances in Water Resources (28) 479-492
The transient storage model (TSM) has been widely used in studies of stream solute transport and fate, with an increasing emphasis on reactive solute transport. In this study we perform sensitivity analyses of a conservative TSM and two different reactive solute transport models...
Loosely bound oxytetracycline in riverine sediments from two tributaries of the Chesapeake Bay
N.S. Simon
2005, Environmental Science & Technology (39) 3480-3487
The fate of antibiotics that bind to riverine sediment is not well understood. A solution used in geochemical extraction schemes to determine loosely bound species in sediments, 1 M MgCl2 (pH 8), was chosen to determine loosely bound, and potentially bioavailable, tetracycline antibiotics (TCs), including oxytetracycline (5-OH tetracycline)...
Assessing the vulnerability of a municipal well field to contamination in a karst aquifer
R.A. Renken, K.J. Cunningham, M.R. Zygnerski, M.A. Wacker, A.M. Shapiro, R.W. Harvey, D.W. Metge, C.L. Osborn, J. N. Ryan
2005, Environmental & Engineering Geoscience (11) 319-331
Proposed expansion of extractive lime-rock mines near the Miami-Dade County Northwest well field and Everglades wetland areas has garnered intense scrutiny by government, public, environmental stakeholders, and the media because of concern that mining will increase the risk of pathogen contamination. Rock mines are excavated to the same depth as...
Simulation of integrated surface-water/ground-water flow and salinity for a coastal wetland and adjacent estuary
C. Langevin, E. Swain, M. Wolfert
2005, Journal of Hydrology (314) 212-234
The SWIFT2D surface-water flow and transport code, which solves the St Venant equations in two dimensions, was coupled with the SEAWAT variable-density ground-water code to represent hydrologic processes in coastal wetlands and adjacent estuaries. A sequentially coupled time-lagged approach was implemented, based on a variable-density form of Darcy's Law, to...
