Population-specific demographic estimates provide insights into declines of Lark Buntings (Calamospiza melanocorys)
A. A. Yackel Adams, S. K. Skagen, J. A. Savidge
2007, The Auk (124) 578-593
Many North American prairie bird populations have recently declined, and the causes of these declines remain largely unknown. To determine whether population limitation occurs during breeding, we evaluated the stability of a population of prairie birds using population-specific values for fecundity and postfledging survival. During 2001-2003, we radiomarked 67 female...
Modeling of gas generation from the Barnett Shale, Fort Worth Basin, Texas
R.J. Hill, E. Zhang, B.J. Katz, Y. Tang
2007, American Association of Petroleum Geologists Bulletin (91) 501-521
The generative gas potential of the Mississippian Barnett Shale in the Fort Worth Basin, Texas, was quantitatively evaluated by sealed gold-tube pyrolysis. Kinetic parameters for gas generation and vitrinite reflectance (Ro) changes were calculated from pyrolysis data and the results used to estimate the amount of gas generated from the...
Close temporal correspondence between geomagnetic anomalies and earthquakes during the 2002-2003 eruption of Etna volcano
G. Currenti, Negro C. Del, M. Johnston, Y. Sasai
2007, Journal of Geophysical Research B: Solid Earth (112)
The early stages of the 2002-2003 lateral eruption at Mount Etna were accompanied by slow changes (over some hours) and some rapid step offsets in the local magnetic field. At five monitoring locations, the total magnetic field intensity has been measured using continuously operating Overhauser magnetometers at a sampling rate...
Patterns and trends in sediment toxicity in the San Francisco Estuary
B. Anderson, J. Hunt, B. Phillips, B. Thompson, S. Lowe, K. Taberski, Carr R. Scott
2007, Environmental Research (105) 145-155
Widespread sediment toxicity has been documented throughout the San Francisco Estuary since the mid-1980s. Studies conducted in the early 1990s as part of the Bay Protection and Toxic Cleanup Program (BPTCP), and more recently as part of the Regional Monitoring Program (RMP) have continued to find sediment toxicity in the...
Species richness and soil properties in Pinus ponderosa forests: A structural equation modeling analysis
D.C. Laughlin, S.R. Abella, W.W. Covington, J.B. Grace
2007, Journal of Vegetation Science (18) 231-242
Question: How are the effects of mineral soil properties on understory plant species richness propagated through a network of processes involving the forest overstory, soil organic matter, soil nitrogen, and understory plant abundance? Location: North-central Arizona, USA. Methods: We sampled 75 0.05-ha plots across a broad soil gradient in a...
Migration of bats past a remote island offers clues toward the problem of bat fatalities at wind turbines
P.M. Cryan, A.C. Brown
2007, Biological Conservation (139) 1-11
Wind energy is rapidly becoming a viable source of alternative energy, but wind turbines are killing bats in many areas of North America. Most of the bats killed by turbines thus far have been migratory species that roost in trees throughout the year, and the highest fatality events appear to...
Estimating hydraulic properties of volcanic aquifers using constant-rate and variable-rate aquifer tests
K. Rotzoll, A. I. El-Kadi, S. B. Gingerich
2007, Journal of the American Water Resources Association (43) 334-345
In recent years the ground-water demand of the population of the island of Maui, Hawaii, has significantly increased. To ensure prudent management of the ground-water resources, an improved understanding of ground-water flow systems is needed. At present, large-scale estimations of aquifer properties are lacking for Maui. Seven analytical methods using...
Nutrients stimulate leaf breakdown rates and detritivore biomass: Bottom-up effects via heterotrophic pathways
J.L. Greenwood, A.D. Rosemond, J.B. Wallace, W. F. Cross, H.S. Weyers
2007, Oecologia (151) 637-649
Most nutrient enrichment studies in aquatic systems have focused on autotrophic food webs in systems where primary producers dominate the resource base. We tested the heterotrophic response to long-term nutrient enrichment in a forested, headwater stream. Our study design consisted of 2 years of pretreatment data in a reference and...
Using a bioenergetic model to assess growth reduction from catch-and-release fishing and hooking injury in rainbow trout, Oncorhynchus mykiss
Julie M. Meka, F.J. Margraf
2007, Fisheries Management and Ecology (14) 131-139
A bioenergetic model was used to predict the potential effects of feeding cessation caused by catch-and-release capture and a reduction in feeding efficiency from hooking injuries on rainbow trout, Oncorhynchus mykiss (Walbaum), growth in southwest Alaska, USA. Simulations indicated that a 1-day feeding cessation for a rainbow trout captured one to two...
Rapid plant diversity assessment using a pixel nested plot design: A case study in Beaver Meadows, Rocky Mountain National Park, Colorado, USA
M. A. Kalkhan, E.J. Stafford, T.J. Stohlgren
2007, Diversity and Distributions (13) 379-388
Geospatial statistical modelling and thematic maps have recently emerged as effective tools for the management of natural areas at the landscape scale. Traditional methods for the collection of field data pertaining to questions of landscape were developed without consideration for the parameters of these applications. We introduce an alternative field...
Erosion and landscape development decouple strontium and sulfur in the transition to dominance by atmospheric inputs
C.R. Bern, S. Porder, A.R. Townsend
2007, Geoderma (142) 274-284
Weathering and leaching can progressively deplete the pools of soluble, rock-derived elements in soils and ecosystems over millennial time-scales, such that productivity increasingly relies on inputs from atmospheric deposition. This transition has been explored using strontium isotopes, which have been widely assumed to be a proxy for the provenance of...
Visible and near-infrared multispectral analysis of rocks at Meridiani Planum, Mars, by the Mars Exploration Rover Opportunity
W. H. Farrand, J.F. Bell III, J. R. Johnson, B.L. Jolliff, A.H. Knoll, S. M. McLennan, S. W. Squyres, W. M. Calvin, J.P. Grotzinger, R.V. Morris, J. Soderblom, S.D. Thompson, W.A. Watters, A. S. Yen
2007, Journal of Geophysical Research E: Planets (112)
Multispectral measurements in the visible and near infrared of rocks at Meridiani Planum by the Mars Exploration Rover Opportunity's Pancam are described. The Pancam multispectral data show that the outcrops of the Burns formation consist of two main spectral units which in stretched 673, 535, 432 nm color composites appear...
Anaerobic biodegradation and hydrogeochemical controls on natural attenuation of trichloroethene in an inland forested wetland
M.M. Lorah, L.J. Dyer, D.R. Burris
2007, Bioremediation Journal (11) 85-102
Anaerobic biodegradation was conducted in a forested wetland where a plume of trichloroethylene discharges from a sand aquifer through organic-rich wetland and stream-bottom sediments. The rapid response of the wetland hydrology to precipitation events altered groundwater flow and geochemistry during wet conditions in the spring compared to the drier conditions...
Local magnitude determinations for intermountain seismic belt earthquakes from broadband digital data
J.C. Pechmann, S.J. Nava, F.M. Terra, J.C. Bernier
2007, Bulletin of the Seismological Society of America (97) 557-574
The University of Utah Seismograph Stations (UUSS) earthquake catalogs for the Utah and Yellowstone National Park regions contain two types of size measurements: local magnitude (ML) and coda magnitude (MC), which is calibrated against ML. From 1962 through 1993, UUSS calculated ML values for southern and central Intermountain Seismic Belt...
A shifting mosaic of scholarly publishing, scientific delivery, and future impact changing the face of learned societies
David M. Leslie Jr.
2007, Journal of Mammalogy (88) 275-286
Nonprofit scientific societies hope that their activities advance their particular mission and impact their profession and, in the broadest sense, humanity in positive ways. The digital age has provided unprecedented mechanisms to enhance the delivery of science to the world. The marketplace of scientific publishing is a rapidly shifting mosaic...
Effects of management and climate on elk brucellosis in the Greater Yellowstone Ecosystem
P.C. Cross, W.H. Edwards, B.M. Scurlock, E.J. Maichak, J.D. Rogerson
2007, Ecological Applications (17) 957-964
Every winter, government agencies feed ∼6000 metric tons (6 × 106 kg) of hay to elk in the southern Greater Yellowstone Ecosystem (GYE) to limit transmission of Brucella abortus, the causative agent of brucellosis, from elk to cattle. Supplemental feeding, however, is likely to increase the transmission of brucellosis in...
Land cover variation and West Nile virus prevalence: Patterns, processes, and implications for disease control
V.O. Ezenwa, L.E. Milheim, M.F. Coffey, M.S. Godsey, R.J. King, S.C. Guptill
2007, Vector-Borne and Zoonotic Diseases (7) 173-180
Identifying links between environmental variables and infectious disease risk is essential to understanding how human-induced environmental changes will effect the dynamics of human and wildlife diseases. Although land cover change has often been tied to spatial variation in disease occurrence, the underlying factors driving the correlations are often unknown, limiting...
USGS assessment of undiscovered oil and gas resources in Paleogene strata of the U.S. Gulf of Mexico coastal plain and state waters
Peter D. Warwick, James L. Coleman, Paul C. Hackley, Daniel O. Hayba, Alexander W. Karlsen, Elisabeth L. Rowan, Sharon M. Swanson
Lorcan Kennan, James Pindell, Norman C. Rosen, editor(s)
2007, Conference Paper, The Paleogene of the Gulf of Mexico and Caribbean basins: Processes, events, and petroleum systems
This report presents a review of the U.S. Geological Survey (USGS) 2007 assessment of the undiscovered oil and gas resources in Paleogene strata underlying the U.S. Gulf of Mexico Coastal Plain and state waters. Geochemical, geologic, geophysical, thermal maturation, burial history, and paleontologic studies have been combined with regional cross...
Eogenetic karst hydrology: Insights from the 2004 hurricanes, peninsular Florida
L.J. Florea, H. Leonard Vacher
2007, Ground Water (45) 439-446
Eogenetic karst lies geographically and temporally close to the depositional environment of limestone in warm marine water at low latitude, in areas marked by midafternoon thunderstorms during a summer rainy season. Spring hydrographs from such an environment in north-central Florida are characterized by smooth, months-long, seasonal maxima. The passage of...
Environmental and ecological conditions surrounding the production of large year classes of walleye (Sander vitreus) in Saginaw Bay, Lake Huron
D.G. Fielder, J.S. Schaeffer, M.V. Thomas
2007, Journal of Great Lakes Research (33) 118-132
The Saginaw Bay walleye population (Sander vitreus) has not fully recovered from a collapse that began in the 1940s and has been dependent on stocking with only limited natural reproduction. Beginning in 2003, and through at least 2005, reproductive success of walleye surged to unprecedented levels. The increase was concurrent...
Suspended sediment transport in an ephemeral stream following wildfire
D.V. Malmon, Steven L. Reneau, D. Katzman, A. Lavine, J. Lyman
2007, Journal of Geophysical Research F: Earth Surface (112)
We examine the impacts of a stand-clearing wildfire on the characteristics and magnitude of suspended sediment transport in ephemeral streams draining the burn area. We report the results of a monitoring program that includes 2 years of data prior to the Cerro Grande fire in...
Using simulated historical time series to prioritize fuel treatments on landscapes across the United States: The LANDFIRE prototype project
Robert E. Keane, Matthew Rollins, Zhi-Liang Zhu
2007, Ecological Modelling (204) 485-502
Canopy and surface fuels in many fire-prone forests of the United States have increased over the last 70 years as a result of modern fire exclusion policies, grazing, and other land management activities. The Healthy Forest Restoration Act and National Fire Plan establish a national commitment to reduce fire hazard...
Regression models for estimating coseismic landslide displacement
R.W. Jibson
2007, Engineering Geology (91) 209-218
Newmark's sliding-block model is widely used to estimate coseismic slope performance. Early efforts to develop simple regression models to estimate Newmark displacement were based on analysis of the small number of strong-motion records then available. The current availability of a much larger set of strong-motion records dictates that these regression...
New K-Ar ages for calculating end-of-shield extrusion rates at West Maui volcano, Hawaiian island chain
David R. Sherrod, T. Murai, Takahiro Tagami
2007, Bulletin of Volcanology (69) 627-642
Thirty-seven new K–Ar ages from West Maui volcano, Hawai‘i, are used to define the waning stages of shield growth and a brief episode of postshield volcanism. All but two samples from shield-stage strata have reversed polarity magnetization, so conceivably the exposed shield is not much older than the Olduvai Normal-Polarity...
Fluid chemistry and evolution of hydrothermal fluids in an Archaean transcrustal fault zone network: The case of the Cadillac Tectonic Zone, Abitibi greenstone belt, Canada
P. Neumayr, S.G. Hagemann, D.A. Banks, B.W.D. Yardley, J.-F. Couture, G. P. Landis, R. Rye
2007, Canadian Journal of Earth Sciences (44) 745-773
Detailed fluid geochemistry studies on hydrothermal quartz veins from the Rouyn-Noranda and Val-d'Or areas along the transcrustal Cadillac Tectonic Zone (CTZ) indicate that unmineralized (with respect to gold) sections of the CTZ contained a distinct CO2-dominated, H2S-poor hydrothermal fluid. In contrast, both gold mineralized sections of the CTZ (e.g., at...
