A rangewide population genetic study of trumpeter swans
S.J. Oyler-McCance, F.A. Ransler, L.K. Berkman, T.W. Quinn
2007, Conservation Genetics (8) 1339-1353
For management purposes, the range of naturally occurring trumpeter swans (Cygnus buccinator) has been divided into two populations, the Pacific Coast Population (PP) and the Rocky Mountain Population (RMP). Little is known about the distribution of genetic variation across the species' range despite increasing pressure to make difficult management decisions...
Transport and degradation of chlorofluorocarbons (CFCs) in the pyritic Rabis Creek aquifer, Denmark
K. Hinsby, Anker L. Højberg, P. Engesgaard, K.H. Jensen, F. Larsen, Niel Plummer, Eurybiades Busenberg
2007, Water Resources Research (43)
Vertical profiles of the chlorofluorocarbons CFC‐11, CFC‐12, and CFC‐113 penetrating aerobic and anaerobic parts of a shallow sandy aquifer show that the CFC gases are degraded in the <1 m thick transition zone from aerobic to anaerobic groundwater in a pyritic sand aquifer at Rabis Creek, Denmark. Two‐dimensional solute transport...
Surface drifter derived circulation in the northern and middle Adriatic Sea: Response to wind regime and season
L. Ursella, P.-M. Poulain, R. P. Signell
2007, Journal of Geophysical Research C: Oceans (112)
More than 120 satellite-tracked drifters were deployed in the northern and middle Adriatic (NMA) Sea between September 2002 and November 2003, with the purpose of studying the surface circulation at mesoscale to seasonal scale in relation to wind forcing, river runoff, and bottom topography. Pseudo-Eulerian and Lagrangian statistics were calculated...
Selected chemical composition of deposited sediments in the flooded areas of New Orleans following Hurricane Katrina
Emitt C. Witt III, Craig Adams, Jianmin Wang, David K. Shaver, Youssef Filali-Meknassi
2007, Circular 1306-7B
Nearly 4 weeks after Hurricane Katrina passed through St. Bernard Parish, the U.S. Geological Survey's (USGS) Mid-Continent Geographic Science Center and the University of Missouri-Rolla's (UMR) Natural Hazard Mitigation Institute deployed a team of scientists to the region to collect perishable environmental and engineering data. The team collected 149 samples...
Sea level fluctuations in central California at subtidal to decadal and longer time scales with implications for San Francisco Bay, California
H. F. Ryan, M.A. Noble
2007, Estuarine, Coastal and Shelf Science (73) 538-550
Sea level elevations from near the mouth of San Francisco Bay are used to describe the low-frequency variability of forcing of the coastal ocean on the Bay at a variety of temporal scales. About 90% of subtidal fluctuations in sea level...
Near-fault peak ground velocity from earthquake and laboratory data
Art McGarr, Joe B. Fletcher
2007, Bulletin of the Seismological Society of America (97) 1502-1510
We test the hypothesis that peak ground velocity (PGV) has an upper bound independent of earthquake magnitude and that this bound is controlled primarily by the strength of the seismogenic crust. The highest PGVs, ranging up to several meters per second, have been measured at sites within a few kilometers...
Arsenic attenuation by oxidized aquifer sediments in Bangladesh
Kenneth G. Stollenwerk, George N. Breit, Alan H. Welch, James C. Yount, John W. Whitney, Andrea L. Foster, M.N. Uddin, R.K. Majumder, N. Ahmed
2007, Science of the Total Environment (379) 133-150
Recognition of arsenic (As) contamination of shallow fluvio-deltaic aquifers in the Bengal Basin has resulted in increasing exploitation of groundwater from deeper aquifers that generally contain low concentrations of dissolved As. Pumping-induced infiltration of high-As groundwater could eventually cause As concentrations in these aquifers to increase. This study investigates the...
Population estimates of Hyla cinerea (Schneider) (Green Tree frog) in an urban environment
L. Pham, S. Boudreaux, S. Karhbet, B. Price, A. S. Ackleh, J. Carter, N. Pal
2007, Southeastern Naturalist (6) 203-216
Hyla cinerea (Green Treefrog) is a common wetlands species in the southeastern US. To better understand its population dynamics, we followed a relatively isolated population of Green Treefrogs from June 2004 through October 2004 at a federal office complex in Lafayette, LA. Weekly, Green Treefrogs were caught, measured, marked with...
Advantages of wet work for near-surface seismic reflection
R. D. Miller, R.D. Markiewicz, T.R. Rademacker, R. Hopkins, R.J. Rawcliffe, J. Paquin
2007, Conference Paper, SEG Technical Program Expanded Abstracts
Benefits of shallow water settings (0.1 to 0.5 m) are pronounced on shallow, high-resolution seismic reflection images and, for examples discussed here, range from an order of magnitude increased signal-to-noise ratio to resolution potential elevated by more than 8 times. Overall data quality of high-resolution seismic reflection data at three...
A simulation-based approach for estimating premining water quality: Red Mountain Creek, Colorado
Robert L. Runkel, Briant A Kimball, Katherine Walton-Day, Philip L. Verplanck
2007, Applied Geochemistry (22) 1899-1918
Regulatory agencies are often charged with the task of setting site-specific numeric water quality standards for impaired streams. This task is particularly difficult for streams draining highly mineralized watersheds with past mining activity. Baseline water quality data obtained prior to mining are often non-existent and application of generic water quality...
Distribution of breeding shorebirds on the Arctic Coastal Plain of Alaska
James A. Johnson, Richard B. Lanctot, Brad A. Andres, Jonathan Bart, Stephen C. Brown, Steven J. Kendall, David C. Payer
2007, Arctic (60) 277-293
Available information on the distribution of breeding shorebirds across the Arctic Coastal Plain of Alaska is dated, fragmented, and limited in scope. Herein, we describe the distribution of 19 shorebird species from data gathered at 407 study plots between 1998 and 2004. This information was collected using a single-visit rapid...
Paleoearthquakes on the southern San Andreas Fault, Wrightwood, California, 3000 to 1500 B.C.: A new method for evaluating paleoseismic evidence and earthquake horizons
K.M. Scharer, R.J. Weldon II, T. E. Fumal, G. P. Biasi
2007, Bulletin of the Seismological Society of America (97) 1054-1093
We present evidence of 11–14 earthquakes that occurred between 3000 and 1500 b.c. on the San Andreas fault at the Wrightwood paleoseismic site. Earthquake evidence is presented in a novel form in which we rank (high, moderate, poor, or low) the quality of all...
Spectral element modelling of fault-plane reflections arising from fluid pressure distributions
M. Haney, R. Snieder, J.-P. Ampuero, R. Hofmann
2007, Geophysical Journal International (170) 933-951
The presence of fault-plane reflections in seismic images, besides indicating the locations of faults, offers a possible source of information on the properties of these poorly understood zones. To better understand the physical mechanism giving rise to fault-plane reflections in compacting sedimentary basins, we numerically model the full elastic wavefield...
River enhancement in the Upper Mississippi River basin: Approaches based on river uses, alterations, and management agencies
T. K. O’Donnell, D.L. Galat
2007, Restoration Ecology (15) 538-549
The Upper Mississippi River is characterized by a series of locks and dams, shallow impoundments, and thousands of river channelization structures that facilitate commercial navigation between Minneapolis, Minnesota, and Cairo, Illinois. Agriculture and urban development over the past 200 years have degraded water quality and increased the rate of sediment...
Analysis of Alaskan burn severity patterns using remotely sensed data
P.A. Duffy, J. Epting, J.M. Graham, T.S. Rupp, A. D. McGuire
2007, International Journal of Wildland Fire (16) 277-284
Wildland fire is the dominant large-scale disturbance mechanism in the Alaskan boreal forest, and it strongly influences forest structure and function. In this research, patterns of burn severity in the Alaskan boreal forest are characterised using 24 fires. First, the relationship between burn severity and area burned is quantified using...
The impact of time and field conditions on brown bear (Ursus arctos) faecal DNA amplification
M.A. Murphy, K.C. Kendall, A. Robinson, L.P. Waits
2007, Conservation Genetics (8) 1219-1224
To establish longevity of faecal DNA samples under varying summer field conditions, we collected 53 faeces from captive brown bears (Ursus arctos) on a restricted vegetation diet. Each faeces was divided, and one half was placed on a warm, dry field site while the other half was placed on a...
Field test comparison of an autocorrelation technique for determining grain size using a digital 'beachball' camera versus traditional methods
P.L. Barnard, D. M. Rubin, J. Harney, N. Mustain
2007, Sedimentary Geology (201) 180-195
This extensive field test of an autocorrelation technique for determining grain size from digital images was conducted using a digital bed-sediment camera, or 'beachball' camera. Using 205 sediment samples and >1200 images from a variety of beaches on the west coast of the US, grain size ranging from sand to...
Biogeographic affinity helps explain productivity-richness relationships at regional and local scales
S. Harrison, J.B. Grace
2007, Conference Paper, American Naturalist
The unresolved question of what causes the observed positive relationship between large-scale productivity and species richness has long interested ecologists and evolutionists. Here we examine a potential explanation that we call the biogeographic affinity hypothesis, which proposes that the productivity-richness relationship is a function of species' climatic tolerances that in...
Rapid assessment of postfire plant invasions in coniferous forests of the western United States
J.P. Freeman, T.J. Stohlgren, M.E. Hunter, Philip N. Omi, E.J. Martinson, G.W. Chong, C. S. Brown
2007, Ecological Applications (17) 1656-1665
Fire is a natural part of most forest ecosystems in the western United States, but its effects on nonnative plant invasion have only recently been studied. Also, forest managers are engaging in fuel reduction projects to lessen fire severity, often without considering potential negative ecological consequences such as nonnative plant...
Prioritizing bottomland hardwood forest sites for protection and augmentation
J. Carter, J. Biagas
2007, Natural Areas Journal (27) 72-82
Bottomland hardwood forest has been greatly diminished by conversion to agriculture. Less than 25% of the pre-Columbian bottomland hardwood forests remain in the southeastern United States. Because of the valuable ecological and hydrological functions performed by these forests, their conservation and restoration has been a high priority. Part of these...
Identifying sources of nitrogen to Hanalei Bay, Kauai, utilizing the nitrogen isotope signature of macroalgae
E. Derse, K.L. Knee, Scott D. Wankel, Carol Kendall, Carl J. Berg Jr., A. Paytan
2007, Environmental Science & Technology (41) 5217-5223
Sewage effluent, storm runoff, discharge from polluted rivers, and inputs of groundwater have all been suggested as potential sources of land derived nutrients into Hanalei Bay, Kauai. We determined the nitrogen isotopic signatures (δ15N) of different nitrate sources to Hanalei Bay...
A three-dimensional geophysical model of the crust in the Barents Sea region: Model construction and basement characterization
O. Ritzmann, N. Maercklin, Faleide J. Inge, H. Bungum, Walter D. Mooney, Shane T. Detweiler
2007, Geophysical Journal International (170) 417-435
BARENTS50, a new 3-D geophysical model of the crust in the Barents Sea Region has been developed by the University of Oslo, NORSAR and the U.S. Geological Survey. The target region comprises northern Norway and Finland, parts of the Kola Peninsula and the East European lowlands. Novaya Zemlya, the...
The viability of a nonenzymatic reductive citric acid cycle - Kinetics and thermochemistry
D.S. Ross
2007, Origins of Life and Evolution of the Biosphere (37) 61-65
The likelihood of a functioning nonenzymatic reductive citric acid cycle, recently proposed as the precursor to biosynthesis on early Earth, is examined on the basis of the kinetics and thermochemistry of the acetate → pyruvate → oxaloacetate → malate sequence. Using data derived from studies of...
Estimating trend precision and power to detect trends across grouped count data
B. R. Gray, M.M. Burlew
2007, Ecology (88) 2364-2372
Ecologists commonly use grouped or clustered count data to estimate temporal trends in counts, abundance indices, or abundance. For example, the U.S. Breeding Bird Survey data represent multiple counts of birds from within each of multiple, spatially defined routes. Despite a reliance on grouped counts, analytical methods for prospectively estimating...
A field assessment of the value of steady shape hydraulic tomography for characterization of aquifer heterogeneities
Geoffrey C. Bohling, James J. Butler Jr., Xiaoyong Zhan, Michael D. Knoll
2007, Water Resources Research (43)
Hydraulic tomography is a promising approach for obtaining information on variations in hydraulic conductivity on the scale of relevance for contaminant transport investigations. This approach involves performing a series of pumping tests in a format similar to tomography. We present a field‐scale assessment of hydraulic tomography in a porous aquifer,...
