Redox processes and water quality of selected principal aquifer systems
P.B. McMahon, F. H. Chapelle
2008, Ground Water (46) 259-271
Reduction/oxidation (redox) conditions in 15 principal aquifer (PA) systems of the United States, and their impact on several water quality issues, were assessed from a large data base collected by the National Water-Quality Assessment Program of the USGS. The logic of these assessments was based on the observed ecological succession...
Effects of turbulence on hydraulic heads and parameter sensitivities in preferential groundwater flow layers
W. Barclay Shoemaker, Kevin J. Cunningham, Eve L. Kuniansky, Joann F. Dixon
2008, Water Resources Research (44)
A conduit flow process (CFP) for the Modular Finite Difference Ground‐Water Flow model, MODFLOW‐2005, has been created by the U.S. Geological Survey. An application of the CFP on a carbonate aquifer in southern Florida is described; this application examines (1) the potential for turbulent groundwater flow and (2) the effects...
Mercury concentrations in salmonids from western U.S. National Parks and relationships with age and macrophage aggregates
A.R. Schwindt, J.W. Fournie, D.H. Landers, C.B. Schreck, M.L. Kent
2008, Environmental Science & Technology (42) 1365-1370
Mercury accumulation in aquatic foodwebs and its effects on aquatic biota are of growing concern both for the health of the fish and the piscivores that prey upon them. This is of particular concern for western U.S. National Parks because it is known that mountainous and Arctic areas are sinks...
Timing and location of mortality of fledgling, subadult, and adult California Gulls
B.H. Pugesek, K.L. Diem
2008, Wilson Journal of Ornithology (120) 159-166
We investigated patterns of mortality during post-breeding migrations of California Gulls (Larus californicus) nesting near Laramie, Wyoming, USA. We used 151 recoveries and 647 sightings of banded and patagially-marked gulls to compare ratios of mortalities to observations of live birds (1) during four time periods (early and late fall migration,...
Non-spore forming eubacteria isolated at an altitude of 20,000 m in Earth's atmosphere: extended incubation periods needed for culture-based assays
Dale W. Griffin
2008, Aerobiologia (24) 19-25
On 13 August 2004, an atmospheric sample was collected at an altitude of 20,000 m along a west to east transect over the continental United States by NASA’s Stratospheric and Cosmic Dust Program. This sample was then shipped to the US Geological Survey’s Global Desert Dust program for microbiological analyses....
Occurrence, distribution and transport of pesticides into the Salton Sea Basin, California, 2001-2002
L.A. LeBlanc, K.M. Kuivila
2008, Hydrobiologia (604) 151-172
The Salton Sea is a hypersaline lake located in southeastern California. Concerns over the ecological impacts of sediment quality and potential human exposure to dust emissions from exposed lakebed sediments resulting from anticipated shrinking of shoreline led to a study of pesticide distribution and transport within the Salton Sea Basin,...
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...
Studies on geological background and source of fluorine in drinking water in the North China Plate fluorosis areas
K. Luo, F. Feng, H. Li, C. L. Chou, Z. Feng, D. Yunshe
2008, Toxicological and Environmental Chemistry (90) 237-246
Endemic fluorosis in northern China is usually produced by high fluorine (F) content in drinking water. Thirty-one samples of drinking waters, mainly well waters and nearly 200 samples of rocks, loess, and coal were analyzed for F content using the combustion hydrolysis-fluoride-ion selective electrode (ISE) method. The geologic cross sections...
Landsat continuity: Issues and opportunities for land cover monitoring
M.A. Wulder, Joanne C. White, S.N. Goward, J. G. Masek, J. R. Irons, M. Herold, W.B. Cohen, Thomas R. Loveland, C. E. Woodcock
2008, Remote Sensing of Environment (112) 955-969
Initiated in 1972, the Landsat program has provided a continuous record of earth observation for 35 years. The assemblage of Landsat spatial, spectral, and temporal resolutions, over a reasonably sized image extent, results in imagery that can be processed to represent land cover over large areas with an amount of spatial...
Space-based detection of wetlands' surface water level changes from L-band SAR interferometry
S. Wdowinski, S.-W. Kim, F. Amelung, T.H. Dixon, F. Miralles-Wilhelm, R. Sonenshein
2008, Remote Sensing of Environment (112) 681-696
Interferometric processing of JERS-1 L-band Synthetic Aperture Radar (SAR) data acquired over south Florida during 1993-1996 reveals detectable surface changes in the Everglades wetlands. Although our study is limited to south Florida it has implication for other large-scale wetlands, because south Florida wetlands have diverse vegetation types and both managed...
Planning riparian restoration in the context of tamarix control in Western North America
P.B. Shafroth, Vanessa B. Beauchamp, M.K. Briggs, K. Lair, M. L. Scott, A.A. Sher
2008, Restoration Ecology (16) 97-112
Throughout the world, the condition of many riparian ecosystems has declined due to numerous factors, including encroachment of non-native species. In the western United States, millions of dollars are spent annually to control invasions of Tamarix spp., introduced small trees or shrubs from Eurasia that have colonized bottomland ecosystems along...
Influence of natural dissolved organic carbon on the bioavailability of mercury to a freshwater alga
P.R. Gorski, D.E. Armstrong, J.P. Hurley, D. P. Krabbenhoft
2008, Environmental Pollution (154) 116-123
Bioavailability of mercury (Hg) to Selenastrum capricornutum was assessed in bioassays containing field-collected freshwater of varying dissolved organic carbon (DOC) concentrations. Bioconcentration factor (BCF) was measured using stable isotopes of methylmercury (MeHg) and inorganic Hg(II). BCFs for MeHg in low-DOC lake water were significantly larger than those in mixtures of...
Transient simulations of nitrogen load for a coastal aquifer and embayment, Cape Cod, MA
J.A. Colman, John P. Masterson
2008, Environmental Science & Technology (42) 207-213
A time-varying, multispecies, modular, three-dimensional transport model (MT3DMS) was developed to simulate groundwater transport of nitrogen from increasing sources on land to the shore of Nauset Marsh, a coastal embayment of the Cape Cod National Seashore. Simulated time-dependent nitrogen loads at the coast can be used to correlate with current...
A basin-scale approach to estimating stream temperatures of tributaries to the lower Klamath River, California
L. E. Flint, A. L. Flint
2008, Journal of Environmental Quality (37) 57-68
Stream temperature is an important component of salmonid habitat and is often above levels suitable for fish survival in the Lower Klamath River in northern California. The objective of this study was to provide boundary conditions for models that are assessing stream temperature on the main stem for the purpose...
Detection of foliage-obscured vehicle using a multiwavelength polarimetric lidar
S. Tan, J. Stoker, S. Greenlee
2008, Conference Paper, International Geoscience and Remote Sensing Symposium (IGARSS)
Foliage obscured man-made targets detection and identification is of great interest to many applications. In this paper, the backscattered laser signals from a multiwavelength polarimetric lidar were used to detect a vehicle hidden inside a vegetated area. The polarimetric reflectance data from the lidar at two separate laser wavelengths at...
Consumption estimates of walleye stocked as fry to suppress fathead minnow populations in west-central Minnesota wetlands
M.C. Ward, D.W. Willis, B.R. Herwig, S. R. Chipps, B.G. Parsons, J.R. Reed, M.A. Hanson
2008, Ecology of Freshwater Fish (17) 59-70
Fisheries managers throughout the Prairie Pothole Region of Minnesota often use semi-permanent and permanent wetland basins to extensively culture walleye Sander vitreus fry. Waterfowl managers have expressed concern over this practice because of the potential influence that fish have on food resources used by waterfowl during development and migration. It...
Economic decision making and the application of nonparametric prediction models
Emil D. Attanasi, Timothy C. Coburn, Philip A. Freeman
2008, SPE Reservoir Evaluation and Engineering (11) 1089-1096
Sustained increases in energy prices have focused attention on gas resources in low-permeability shale or in coals that were previously considered economically marginal. Daily well deliverability is often relatively small, although the estimates of the total volumes of recoverable resources in these settings are often large. Planning and development decisions...
Metalliferous sediment and a silica-hematite deposit within the Blanco fracture zone, Northeast Pacific
J.R. Hein, D.A. Clague, R.A. Koski, R.W. Embley, R.E. Dunham
2008, Marine Georesources and Geotechnology (26) 317-339
A Tiburon ROV dive within the East Blanco Depression (EBD) increased the mapped extent of a known hydrothermal field by an order of magnitude. In addition, a unique opal-CT (cristobalite-tridymite)-hematite mound was discovered, and mineralized sediments and rock were collected and analyzed. Silica-hematite mounds have not previously been found on...
Mineral resource of the month: vermiculite
M.J. Potter
2008, Geotimes (53) 20-21
Vermiculite, a hydrated magnesium-aluminum-iron silicate mineral, has a range of uses that take advantage of its fire resistance, good insulating properties, high liquid absorption capacity, inertness and low density. Most applications for vermiculite use an exfoliated (heat-expanded) form of the mineral. In general, coarser grades of vermiculite are used as...
Change in the forested and developed landscape of the Lake Tahoe basin, California and Nevada, USA, 1940-2002
C.G. Raumann, Mary E. Cablk
2008, Forest Ecology and Management (255) 3424-3439
The current ecological state of the Lake Tahoe basin has been shaped by significant landscape-altering human activity and management practices since the mid-1850s; first through widespread timber harvesting from the 1850s to 1920s followed by urban development from the 1950s to the present. Consequences of landscape change, both from development...
New estimates of lethality of sea lamprey (Petromyzon marinus) attacks on lake trout (Salvelinus namaycush): Implications for fisheries management
C.P. Madenjian, B.D. Chipman, J.E. Marsden
2008, Canadian Journal of Fisheries and Aquatic Sciences (65) 535-542
Sea lamprey (Petromyzon marinus) control in North America costs millions of dollars each year, and control measures are guided by assessment of lamprey-induced damage to fisheries. The favored prey of sea lamprey in freshwater ecosystems has been lake trout (Salvelinus namaycush). A key parameter in assessing sea lamprey damage, as...
Challenges of DNA-based mark-recapture studies of American black bears
K.E. Settlage, F.T. Van Manen, J. D. Clark, T.L. King
2008, Journal of Wildlife Management (72) 1035-1042
We explored whether genetic sampling would be feasible to provide a region-wide population estimate for American black bears (Ursus americanus) in the southern Appalachians, USA. Specifically, we determined whether adequate capture probabilities (p >0.20) and population estimates with a low coefficient of variation (CV <20%) could be achieved given typical agency...
Simulating water, solute, and heat transport in the subsurface with the VS2DI software package
R. W. Healy
2008, Vadose Zone Journal (7) 632-639
The software package VS2DI was developed by the U.S. Geological Survey for simulating water, solute, and heat transport in variably saturated porous media. The package consists of a graphical preprocessor to facilitate construction of a simulation, a postprocessor for visualizing simulation results, and two numerical models that solve for flow...
Bioaccumulation of pharmaceuticals and other anthropogenic waste indicators in earthworms from agricultural soil amended with biosolid or swine manure
C.A. Kinney, E. T. Furlong, D.W. Kolpin, M.R. Burkhardt, S.D. Zaugg, S.L. Werner, J.P. Bossio, M.J. Benotti
2008, Environmental Science & Technology (42) 1863-1870
Analysis of earthworms offers potential for assessing the transfer of organic anthropogenic waste indicators (AWIs) derived from land-applied biosolid or manure to biota. Earthworms and soil samples were collected from three Midwest agricultural fields to measure the presence and potential for transfer of 77 AWIs from land-applied...
Ground-motion modeling of the 1906 San Francisco earthquake, part I: Validation using the 1989 Loma Prieta earthquake
Brad T. Aagaard, T.M. Brocher, D. Dolenc, D. Dreger, R.W. Graves, S. Harmsen, S. Hartzell, S. Larsen, M.L. Zoback
2008, Bulletin of the Seismological Society of America (98) 989-1011
We compute ground motions for the Beroza (1991) and Wald et al. (1991) source models of the 1989 magnitude 6.9 Loma Prieta earthquake using four different wave-propagation codes and recently developed 3D geologic and seismic velocity models. In preparation for modeling the 1906 San Francisco earthquake, we use this well-recorded...
