Compound-specific carbon isotope analysis of a contaminant plume in Kingsford, Michigan, USA
R. L. Michel, S. R. Silva, B. Bemis, E.M. Godsy, E. Warren
2001, IAHS-AISH Publication 311-316
Compound-specific isotope analysis was used to study a contaminated site near Kingsford, Michigan, USA. Organic compounds at three of the sites studied had similar 13C values indicating that the contaminant source is the same for all sites. At a fourth site, chemical and 13C values had evolved due to microbial...
Long-term changes in consentrations and flux fo nitrogen in the Mississippi River Basin, USA
D. A. Goolsby, W.A. Battaglin
2001, Hydrological Processes (15) 1209-1226
Current and historical data show that nitrogen concentrations and flux in the Mississippi River Basin have increased significantly during the past 100 years. Most of the increase observed in the lower Mississippi River has occurred since the early 1970s and is due almost entirely to an increase in nitrate. The...
Possible environmental factors underlying amphibian decline in eastern Puerto Rico: Analysis of U.S. government data archives
R.F. Stallard
2001, Conservation Biology (15) 943-953
The past three decades have seen major declines in populations of several species of amphibians at high elevations in eastern Puerto Rico, a region unique in the humid tropics because of the degree of environmental monitoring that has taken place through the efforts of U.S. government agencies. I examined changes...
Effect of canopy removal on snowpack quantity and quality, fraser experimental forest, Colorado
R. Stottlemyer, C.A. Troendle
2001, Journal of Hydrology (245) 165-176
Snowpack peak water equivalent (PWE), ion concentration, content, and spatial distribution of ion load data from spring 1987-1996 in a 1 ha clearcut and adjacent forested plots vegetated by mature Picea engelmannii and Abies lasiocarpa in the Fraser experimental forest (FEF), Colorado are presented. Our objectives were: (1) to see...
Sulfate-reducing bacteria release barium and radium from naturally occurring radioactive material in oil-field barite
Elizabeth J.P. Phillips, E. R. Landa, T. Kraemer, R. Zielinski
2001, Geomicrobiology Journal (18) 167-182
Scale and sludge deposits formed during oil production can contain elevated levels of Ra, often coprecipitated with barium sulfate (barite). The potential for sulfate-reducing bacteria to release 226 Ra and Ba (a Ra analog) from oil-field barite was evaluated. The concentration of dissolved Ba increased when samples containing pipe scale,...
Timescales for nitrate contamination of spring waters, northern Florida, USA
B. G. Katz, J.K. Böhlke, H.D. Hornsby
2001, Chemical Geology (179) 167-186
Residence times of groundwater, discharging from springs in the middle Suwannee River Basin, were estimated using chlorofluorocarbons (CFCs), tritium (3H), and tritium/helium-3 (3H/3He) age-dating methods to assess the chronology of nitrate contamination of spring waters in northern Florida. During base-flow conditions for the Suwannee River in 1997–1999, 17 water samples...
Laboratory and field evaluations of the LISST-100 instrument for suspended particle size determinations
J. W. Gartner, R. T. Cheng, P.-F. Wang, K. Richter
2001, Marine Geology (175) 199-219
Advances in technology have resulted in a new instrument that is designed for in-situ determination of particle size spectra. Such an instrument that can measure undisturbed particle size distributions is much needed for sediment transport studies. The LISST-100 (Laser In-Situ Scattering and Transmissometry)...
Hydrology of the coastal sabkhas of Abu Dhabi, United Arab Emirates
Ward E. Sanford, Warren W. Wood
2001, Hydrogeology Journal (9) 358-366
Water fluxes were estimated and a water budget developed for the land surface and a surficial 10-m-deep section of the coastal sabkhas that extend from the city of Abu Dhabi, United Arab Emirates, west to the border with Saudi Arabia. The fluxes were estimated on the basis of water levels...
Formation and transport of the sulfonic acid metabolites of alachlor and metolachlor in soil
D.S. Aga, E.M. Thurman
2001, Environmental Science & Technology (35) 2455-2460
Alachlor and metolachlor are dechlorinated and transformed into their corresponding ethane sulfonic acid (ESA) metabolites in soil. In a field-disappearance study, it was shown that alachlor ESA was formed at a faster rate and at concentrations 2−4 times higher than metolachlor ESA, conforming with the observed longer...
Factors controlling the configuration of the fresh-saline water interface in the Dead Sea coastal aquifers: Synthesis of TDEM surveys and numerical groundwater modeling
Y. Yechieli, U. Kafri, M. Goldman, C.I. Voss
2001, Hydrogeology Journal (9) 367-377
TDEM (time domain electromagnetic) traverses in the Dead Sea (DS) coastal aquifer help to delineate the configuration of the interrelated fresh-water and brine bodies and the interface in between. A good linear correlation exists between the logarithm of TDEM resistivity and the chloride concentration of groundwater, mostly in the higher...
Effects of urbanization on streamflow in the Atlanta area (Georgia, USA): A comparative hydrological approach
S. Rose, N.E. Peters
2001, Hydrological Processes (15) 1441-1457
For the period from 1958 to 1996, streamflow characteristics of a highly urbanized watershed were compared with less-urbanized and non-urbanized watersheds within a 20 000 km2 region in the vicinity of Atlanta, Georgia: In the Piedmont and Blue Ridge physiographic provinces of the southeastern USA. Water levels in several wells...
A partition-limited model for the plant uptake of organic contaminants from soil and water
C. T. Chiou, G. Sheng, M. Manes
2001, Environmental Science & Technology (35) 1437-1444
In dealing with the passive transport of organic contaminants from soils to plants (including crops), a partition-limited model is proposed in which (i) the maximum (equilibrium) concentration of a contaminant in any location in the plant is determined by partition equilibrium with its concentration in the soil...
Methyl t-Butyl Ether Mineralization in Surface-Water Sediment Microcosms under Denitrifying Conditions
P. M. Bradley, F. H. Chapelle, J. E. Landmeyer
2001, Applied and Environmental Microbiology (67) 1975-1978
Mineralization of [U-14C] methyl t-butyl ether (MTBE) to 14CO2 without accumulation of t-butyl alcohol (TBA) was observed in surface-water sediment microcosms under denitrifying conditions. Methanogenic activity and limited transformation of MTBE to TBA were observed in the absence of denitrification. Results indicate that bed sediment microorganisms can effectively degrade MTBE...
Assessing an open-well aquifer test in fractured crystalline rock
C. R. Tiedeman, P. A. Hsieh
2001, Ground Water (39) 68-78
Use of open wells to conduct aquifer tests in fractured crystalline rock aquifers is potentially problematic, because open wells can hydraulically connect highly permeable fracture zones at different depths within the rock. Because of this effect, it is questionable whether estimates of the hydraulic properties of the rock obtained from...
Droughts, epic droughts and droughty centuries - lessons from a California paleoclimatic record: a PACLIM 2001 meeting report
M. D. Dettinger
2001, Interagency Ecological Program Newsletter (14) 51-53
During the early 1990s (but echoing studies by S.T. Harding at the University of California, from as early as the 1930s), several lines of paleoclimate evidence in and around the Sierra Nevada Range have provided the water community in California with some real horror stories. By studying ancient tree stumps...
Water sustainability -- Science or management?
Warren W. Wood
2001, Groundwater (39) 641-641
No abstract available ...
In situ spectroscopic and solution analyses of the reductive dissolution of Mn02 by Fe(II)
John E. Villinski, Peggy A. O’Day, Timothy L. Corley, Martha H. Conklin
2001, Environmental Science & Technology (35) 1157-1163
The reductive dissolution of MnO2 by Fe(II) under conditions simulating acid mine drainage (pH 3, 100 mM SO42-) was investigated by utilizing a flow-through reaction cell and synchrotron X-ray absorption spectroscopy. This configuration allows collection of in situ, real-time X-ray absorption near-edge structure (XANES) spectra and bulk solution samples. Analysis...
Analysis of streambed temperatures in ephemeral channels to determine streamflow frequency and duration
James E. Constantz, David A. Stonestrom, Amy E. Stewart, Richard G. Niswonger, Tyson R. Smith
2001, Water Resources Research (37) 317-328
Spatial and temporal patterns in streamflow are rarely monitored for ephemeral streams. Flashy, erosive streamflows common in ephemeral channels create a series of operational and maintenance problems, which makes it impractical to deploy a series of gaging stations along ephemeral channels. Streambed temperature is a robust and inexpensive parameter to...
Post-fire, rainfall intensity-peak discharge relations for three mountainous watersheds in the Western USA
J. A. Moody, D.A. Martin
2001, Hydrological Processes (15) 2981-2993
Wildfire alters the hydrologic response of watersheds, including the peak discharges resulting from subsequent rainfall. Improving predictions of the magnitude of flooding that follows wildfire is needed because of the increase in human population at risk in the wildland-urban interface. Because this wildland-urban interface is typically in mountainous terrain, we...
Simulation of a semi-permanent wetland basin in the Cottonwood Lake area, east-central North Dakota
R.W.H. Carroll, G.M. Pohll, J.C. Tracy, T. C. Winter
Hayes D.F.Hayes D.F., editor(s)
2001, Conference Paper, Proceedings of the 2001 Wetlands Engineering and River Restoration Conference
A coupled surface/subsurface hydrologic model was developed to examine the effects of climatic conditions on stage fluctuations within a semi-permanent wetland located in the Prairie Pothole region of east-central North Dakota. Model calibration was accomplished using data collected from 1981 to 1996 to encompass extreme climatic conditions. Results show that...
A process for fire-related debris flow initiation, Cerro Grande fire, New Mexico
S.H. Cannon, E.R. Bigio, E. Mine
2001, Hydrological Processes (15) 3011-3023
In this study we examine factors that pertain to the generation of debris flows from a basin recently burned by wildfire. Throughout the summer 2000 thunderstorm season, we monitored rain gauges, channel cross-sections, hillslope transects, and nine sediment-runoff traps deployed in a steep, 0??15 km2 basin burned by the May...
Development and application of a spatial hydrology model of Okefenokee Swamp, Georgia
C.S. Loftin, W.M. Kitchens, N. Ansay
2001, Journal of the American Water Resources Association (37) 935-956
The model described herein was used to assess effects of the Suwannee River sill (a low earthen dam constructed to impound the Suwannee River within the Okefenokee National Wildlife Refuge to eliminate wildfires) on the hydrologic environment of Okefenokee Swamp, Georgia. Developed with Arc/Info Macro Language routines in the GRID...
Modelling middle pliocene warm climates of the USA
A.M. Haywood, P.J. Valdes, B.W. Sellwood, J.O. Kaplan, H.J. Dowsett
2001, Palaeontologia Electronica (4)
The middle Pliocene warm period represents a unique time slice in which to model and understand climatic processes operating under a warm climatic regime. Palaeoclimatic model simulations, focussed on the United States of America (USA), for the middle Pliocene (ca 3 Ma) were generated using the USGS PRISM2 2?? ??...
Fulvic acid-sulfide ion competition for mercury ion binding in the Florida everglades
Michael M. Reddy, George Aiken
2001, Water, Air, & Soil Pollution (132) 89-104
Negatively charged functional groups of fulvic acid compete with inorganic sulfide ion for mercury ion binding. This competition is evaluated here by using a discrete site-electrostatic model to calculate mercury solution speciation in the presence of fulvic acid. Model calculated species distributions are used to estimate a mercury-fulvic acid apparent...
Hydrology of Yucca Mountain, Nevada
A. L. Flint, L. E. Flint, E. M. Kwicklis, G.S. Bodvarsson, J. M. Fabryka-Martin
2001, Reviews of Geophysics (39) 447-470
Yucca Mountain, located in southern Nevada in the Mojave Desert, is being considered as a geologic repository for high-level radioactive waste. Although the site is arid, previous studies indicate net infiltration rates of 5-10 mm yr-1 under current climate conditions. Unsaturated flow of water through the mountain generally is vertical...
