Denitrification potential in stream sediments impacted by acid mine drainage: Effects of pH, various electron donors, and iron
J.L. Baeseman, R. L. Smith, J. Silverstein
2006, Microbial Ecology (51) 232-241
Acid mine drainage (AMD) contaminates thousands of kilometers of stream in the western United States. At the same time, nitrogen loading to many mountain watersheds is increasing because of atmospheric deposition of nitrate and increased human use. Relatively little is known about nitrogen cycling in acidic, heavy-metal-laden streams; however,...
Atmospheric dust in modern soil on aeolian sandstone, Colorado Plateau (USA): Variation with landscape position and contribution to potential plant nutrients
Richard L. Reynolds, J. Neff, Marith C. Reheis, Paul J. Lamothe
2006, Geoderma (130) 108-123
Rock-derived nutrients in soils originate from both local bedrock and atmospheric dust, including dust from far-distant sources. Distinction between fine particles derived from local bedrock and from dust provides better understanding of the landscape-scale distribution and abundance of soil nutrients. Sandy surficial deposits over dominantly sandstone substrates, covering vast upland...
Kinetics of sorption and abiotic oxidation of arsenic(III) by aquifer materials
A. Amirbahman, D.B. Kent, G.P. Curtis, J.A. Davis
2006, Geochimica et Cosmochimica Acta (70) 533-547
The fate of arsenic in groundwater depends largely on its interaction with mineral surfaces. We investigated the kinetics of As(III) oxidation by aquifer materials collected from the USGS research site at Cape Cod, MA, USA, by conducting laboratory experiments. Five different solid samples with similar specific surface areas (0.6–0.9 m2 g−1) and...
Influence of landscape-scale factors in limiting brook trout populations in Pennsylvania streams
P.M. Kocovsky, R.F. Carline
2006, Transactions of the American Fisheries Society (135) 76-88
Landscapes influence the capacity of streams to produce trout through their effect on water chemistry and other factors at the reach scale. Trout abundance also fluctuates over time; thus, to thoroughly understand how spatial factors at landscape scales affect trout populations, one must assess the changes in populations over time...
Presence and distribution of wastewater-derived pharmaceuticals in soil irrigated with reclaimed water
C.A. Kinney, E. T. Furlong, S.L. Werner, J.D. Cahill
2006, Environmental Toxicology and Chemistry (25) 317-326
Three sites in the Front Range of Colorado, USA, were monitored from May through September 2003 to assess the presence and distribution of pharmaceuticals in soil irrigated with reclaimed water derived from urban wastewater. Soil cores were collected monthly, and 19 pharmaceuticals, all of which were...
Scaling uncertainties in estimating canopy foliar maintenance respiration for black spruce ecosystems in Alaska
X. Zhang, A. D. McGuire, Roger W. Ruess
2006, Mitigation and Adaptation Strategies for Global Change (11) 147-174
A major challenge confronting the scientific community is to understand both patterns of and controls over spatial and temporal variability of carbon exchange between boreal forest ecosystems and the atmosphere. An understanding of the sources of variability of carbon processes at fine scales and how these contribute to uncertainties in...
A new species of freshwater mussel (Bivalvia: Unionidae), Pleurobema athearni, from the Coosa River Drainage of Alabama, USA
M.M. Gangloff, J.D. Williams, J.W. Feminella
2006, Zootaxa 43-56
The Mobile Basin historically supported one of the most diverse freshwater mussel (Bivalvia: Unionidae) assemblages in North America. More than 65 species of mussels are known from the Basin, but it is difficult to determine how many species were present historically. The drainage's unique physical habitat was largely destroyed between...
The quest for the perfect gravity anomaly: Part 1 - New calculation standards
X. Li, T.G. Hildenbrand, W. J. Hinze, Gordon R. Keller, D. Ravat, M. Webring
2006, SEG Technical Program Expanded Abstracts (25) 859-863
The North American gravity database together with databases from Canada, Mexico, and the United States are being revised to improve their coverage, versatility, and accuracy. An important part of this effort is revision of procedures and standards for calculating gravity anomalies taking into account our enhanced computational power, modern satellite-based...
Time-lapse seismic study of levees in southern New Mexico
J. Ivanov, R. D. Miller, N. Stimac, R.F. Ballard Jr., J. Joseph Dunbar, S. Steve Smullen
2006, SEG Technical Program Expanded Abstracts (25) 3255-3259
The primary objective of this work was to measure changes in compressional- (Vp) and shear-wave (Vs) velocities in an earthen levee during a ponding experiment designed to simulate flood conditions on the Rio Grande in south New Mexico. Although similar to such experiment, performed an year earlier on the Rio...
Detrital zircon provenance of the Late Triassic Songpan-Ganzi complex: Sedimentary record of collision of the North and South China blocks
Amy Weislogel, Stephan A. Graham, E. Z. Chang, Joseph L. Wooden, George E. Gehrels, H. Yang
2006, Geology (34) 97-100
Using detrital zircon geochronology, turbidite deposystems fed from distinct sediment sources can be distinguished within the Songpan-Ganzi complex, a collapsed Middle to Late Triassic turbidite basin of central China. A southern Songpan-Ganzi deposystem initially was sourced solely by erosion of the Qinling-Dabie orogen during early Late Triassic time, then by...
Lake Sturgeon, Acipenser fulvescens, movements in Rainy Lake, Minnesota and Ontario
W.E. Adams Jr., L.W. Kallemeyn, D.W. Willis
2006, Canadian Field-Naturalist (120) 71-82
Rainy Lake, Minnesota-Ontario, contains a native population of Lake Sturgeon (Acipenser fulvescens) that has gone largely unstudied. The objective of this descriptive study was to summarize generalized Lake Sturgeon movement patterns through the use of biotelemetry. Telemetry data reinforced the high utilization of the Squirrel Falls geographic location by Lake...
Detection probabilities and site occupancy estimates for amphibians at Okefenokee National Wildlife Refuge
L. L. Smith, W.J. Barichivich, J.S. Staiger, Kimberly G. Smith, C.K. Dodd Jr.
2006, American Midland Naturalist (155) 149-161
We conducted an amphibian inventory at Okefenokee National Wildlife Refuge from August 2000 to June 2002 as part of the U.S. Department of the Interior's national Amphibian Research and Monitoring Initiative. Nineteen species of amphibians (15 anurans and 4 caudates) were documented within the Refuge, including one protected species, the...
Geology of the Yucca Mountain region
J. S. Stuckless, Dennis W. O’Leary
2006, Memoir of the Geological Society of America (199) 9-50
Yucca Mountain has been proposed as the site for the nation's first geologic repository for high-level radioactive waste. This chapter provides the geologic framework for the Yucca Mountain region. The regional geologic units range in age from late Precambrian through Holocene, and these are described briefly. Yucca Mountain is composed...
Diagenetic alteration of impact spherules in the Neoarchean Monteville layer, South Africa
I. Kohl, B.M. Simonson, M. Berke
2006, Special Paper of the Geological Society of America 57-73
Intercontinental correlation of distal Archean impact ejecta layers can be used to help create a global time-stratigraphic framework for early Earth events. For example, an impact spherule layer in the Neoarchean Monteville Formation (Griqualand West Basin, South Africa) may be correlated with layers in one or more formations in Western...
Mineral of the month: tungsten
Kim B. Shedd
2006, Geotimes (2006)
Tungsten has the highest melting point of all metals, one of the highest densities and, when combined with carbon, is almost as hard as diamond. These and other properties make it useful in a wide variety of important commercial, industrial and military applications....
Trophic structure and avian communities across a salinity gradient in evaporation ponds of the San Francisco Bay estuary
John Y. Takekawa, A.K. Miles, D. H. Schoellhamer, N.D. Athearn, M. K. Saiki, W.D. Duffy, S. Kleinschmidt, G.G. Shellenbarger, C.A. Jannusch
2006, Hydrobiologia (567) 307-327
Commercial salt evaporation ponds comprise a large proportion of baylands adjacent to the San Francisco Bay, a highly urbanized estuary. In the past two centuries, more than 79% of the historic tidal wetlands in this estuary have been lost. Resource management agencies have acquired more than 10 000 ha of commercial salt...
Genetic structure of Cantharellus formosus populations in a second-growth temperate rain forest of the Pacific Northwest
Regina S. Redman, Judith Ranson, Rusty J. Rodriguez
2006, Pacific Northwest Fungi (1) 1-13
Cantharellus formosus growing on the Olympic Peninsula of the Pacific Northwest was sampled from September – November 1995 for genetic analysis. A total of ninety-six basidiomes from five clusters separated from one another by 3 - 25 meters were genetically characterized by PCR analysis of 13 arbitrary loci and rDNA sequences. The number...
Advances in recreational water quality monitoring at Indiana Dunes National Lakeshore
Wendy Smith, Meredith Nevers, Richard L. Whitman
2006, Park Science (24) 19-23
Indiana Dunes has improved its ability to protect the health of swimmers through better science-based management and increased understanding of contaminants. Most research has focused on Escherichia coli and its nature, sources, and distribution because it is widely accepted as an indicator of potential pathogens. Though research on E. coli...
Flow convergence caused by a salinity minimum in a tidal channel
John C. Warner, David H. Schoellhamer, Jon R. Burau, S. Geoffrey Schladow
2006, San Francisco Estuary and Watershed Science (4) 91-102
Residence times of dissolved substances and sedimentation rates in tidal channels are affected by residual (tidally averaged) circulation patterns. One influence on these circulation patterns is the longitudinal density gradient. In most estuaries the longitudinal density gradient typically maintains a constant direction. However, a junction of tidal channels can create...
Cassini/VIMS hyperspectral observations of the HUYGENS landing site on Titan
S. Rodriguez, Stéphane Le Mouélic, Christophe Sotin, H. Clenet, R. N. Clark, B. Buratti, R. H. Brown, T. B. McCord, P. D. Nicholson, K. H. Baines
2006, Planetary and Space Science (54) 1510-1523
Titan is one of the primary scientific objectives of the NASA-ESA-ASI Cassini-Huygens mission. Scattering by haze particles in Titan's atmosphere and numerous methane absorptions dramatically veil Titan's surface in the visible range, though it can be studied more easily in some narrow infrared windows. The Visual and Infrared Mapping Spectrometer...
Are southern California's fragmented saltmarshes capable of sustaining endemic bird populations?
A.N. Powell
Greenberg R.Maldonado J.E.Droege S.McDonald M.V., editor(s)
2006, Studies in Avian Biology 198-204
Loss of coastal saltmarshes in southern California has been estimated at 75-90% since presettlement times. The remaining wetlands are mostly fragmented and degraded, and most frequently have harsh edges adjacent to urban landscapes. Non-migratory Belding's Savannah Sparrows (Passerculus sandwichensis beldingi) and Light-footed Clapper Rails (Rallus longirostris levipes) are endemic to...
Distribution of stress drop, stiffness, and fracture energy over earthquake rupture zones
Joe B. Fletcher, Art McGarr
2006, Journal of Geophysical Research B: Solid Earth (111)
Using information provided by slip models and the methodology of McGarr and Fletcher (2002), we map static stress drop, stiffness (k = ????/u, where ???? is static stress drop and u is slip), and fracture energy over the slip surface to investigate the earthquake rupture process and energy budget. For...
Tracking the movements of Denali's wolves
T.J. Meier, John W. Burch, Layne G. Adams
2006, Alaska Park Science
The wolves of Denali National Park (formerly Mount McKinley National Park) were the subject of some of the earliest research on wolf ecology. From 1939 to 1941, Adolph Murie performed groundbreaking studies of wolves, observing wolves and their prey and collecting wolf scats and prey remains. His work resulted in...
Mallard brood movements, wetland use, and duckling survival during and following a prairie drought
Gary L. Krapu, P.J. Pietz, D.A. Brandt, R. R. Cox Jr.
2006, Journal of Wildlife Management (70) 1436-1444
We used radiotelemetry to study mallard (Anas platyrhynchos) brood movements, wetland use, and duckling survival during a major drought (1988-1992) and during the first 2 years of the subsequent wet period (1993-1994) at 4 51-km2 sites in prairie pothole landscapes in eastern North Dakota, USA. About two-thirds of 69 radiomarked...
Late Pleistocene outburst flooding from pluvial Lake Alvord into the Owyhee River, Oregon
D.T. Carter, L.L. Ely, J. E. O’Connor, C.R. Fenton
2006, Geomorphology (75) 346-367
At least one large, late Pleistocene flood traveled into the Owyhee River as a result of a rise and subsequent outburst from pluvial Lake Alvord in southeastern Oregon. Lake Alvord breached Big Sand Gap in its eastern rim after reaching an elevation of 1292 m, releasing 11.3 km3 of water...
