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Page 743, results 18551 - 18575

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Publication Extents

Not all publications have extents, not all extents are completely accurate
New seismic hazard maps for Puerto Rico and the U.S. Virgin Islands
Charles S. Mueller, Arthur D. Frankel, Mark D. Petersen, Edgar V. Leyendecker
2010, Earthquake Spectra (26) 169-185
The probabilistic methodology developed by the U.S. Geological Survey is applied to a new seismic hazard assessment for Puerto Rico and the U.S. Virgin Islands. Modeled seismic sources include gridded historical seismicity, subduction-interface and strike-slip faults with known slip rates, and two broad zones of crustal extension with seismicity rates...
The ecological limits of hydrologic alteration (ELOHA): A new framework for developing regional environmental flow standards
N.L. Poff, B. D. Richter, A.H. Arthington, S.E. Bunn, R.J. Naiman, E. Kendy, M. Acreman, C. Apse, B.P. Bledsoe, Mary C. Freeman, J. Henriksen, R. B. Jacobson, J.G. Kennen, D.M. Merritt, J. H. O’Keeffe, J. D. Olden, K. Rogers, R.E. Tharme, A. Warner
2010, Freshwater Biology (55) 147-170
The flow regime is a primary determinant of the structure and function of aquatic and riparian ecosystems for streams and rivers. Hydrologic alteration has impaired riverine ecosystems on a global scale, and the pace and intensity of human development greatly exceeds the ability of scientists to assess the effects on...
Color imaging of Mars by the High Resolution Imaging Science Experiment (HiRISE)
W. Alan Delamere, Livio L. Tornabene, Alfred S. McEwen, Kris J. Becker, James W. Bergstrom, Nathan T. Bridges, Eric M. Eliason, Dennis Gallagher, Kenneth E. Herkenhoff, Laszlo P. Keszthelyi, Sarah Mattson, Guy K. McArthur, Michael T. Mellon, Moses P. Milazzo, Patrick S. Russell, Nicolas Thomas
2010, Icarus (205) 38-52
HiRISE has been producing a large number of scientifically useful color products of Mars and other planetary objects. The three broad spectral bands, coupled with the highly sensitive 14 bit detectors and time delay integration, enable detection of subtle color differences. The very high spatial resolution of HiRISE can augment...
Using occupancy models to understand the distribution of an amphibian pathogen, Batrachochytrium dendrobatidis
M. J. Adams, Nathan Chelgren, David M. Reinitz, Rebecca A. Cole, L.J. Rachowicz, Stephanie Galvan, Brome McCreary, Christopher A. Pearl, Larissa L. Bailey, Jamie B. Bettaso, Evelyn L. Bull, Matthias Leu
2010, Ecological Applications (20) 289-302
Batrachochytrium dendrobatidis is a fungal pathogen that is receiving attention around the world for its role in amphibian declines. Study of its occurrence patterns is hampered by false negatives: the failure to detect the pathogen when it is present. Occupancy models are a useful but currently underutilized tool for analyzing...
Regional seismic stratigraphy and controls on the Quaternary evolution of the Cape Hatteras region of the Atlantic passive margin, USA
D. J. Mallinson, S.J. Culver, S.R. Riggs, E.R. Thieler, D. Foster, J. Wehmiller, K.M. Farrell, J. Pierson
2010, Marine Geology (268) 16-33
Seismic and core data, combined with amino acid racemization and strontium-isotope age data, enable the definition of the Quaternary stratigraphic framework and recognition of geologic controls on the development of the modern coastal system of North Carolina, U.S.A. Seven regionally continuous high amplitude reflections are defined which bound six seismic...
Estimating black bear density using DNA data from hair snares
B. Gardner, J. Andrew Royle, M.T. Wegan, R.E. Rainbolt, Paul D. Curtis
2010, Journal of Wildlife Management (74) 318-325
DNA-based mark-recapture has become a methodological cornerstone of research focused on bear species. The objective of such studies is often to estimate population size; however, doing so is frequently complicated by movement of individual bears. Movement affects the probability of detection and the assumption of closure of the population required...
The role of effective discharge in the ocean delivery of particulate organic carbon by small, mountainous river systems
R. A. Wheatcroft, M.A. Goni, J.A. Hatten, G.B. Pasternack, J.A. Warrick
2010, Limnology and Oceanography (55) 161-171
Recent research has shown that small, mountainous river systems (SMRS) account for a significant fraction of the global flux of sediment and particulate organic carbon (POC) to the ocean. The enormous number of SMRS precludes intensive studies of the sort conducted on large systems, necessitating development of a conceptual framework...
Irrigated areas of India derived using MODIS 500 m time series for the years 2001-2003
V. Dheeravath, P.S. Thenkabail, G. Chandrakantha, P. Noojipady, G.P.O. Reddy, C.M. Biradar, M.K. Gumma, M. Velpuri
2010, ISPRS Journal of Photogrammetry and Remote Sensing (65) 42-59
The overarching goal of this research was to develop methods and protocols for mapping irrigated areas using a Moderate Resolution Imaging Spectroradiometer (MODIS) 500 m time series, to generate irrigated area statistics, and to compare these with ground- and census-based statistics. The primary mega-file data-cube (MFDC), comparable to a hyper-spectral...
Propagule pressure and stream characteristics influence introgression: Cutthroat and rainbow trout in British Columbia
S.N. Bennett, J.R. Olson, J. L. Kershner, P. Corbett
2010, Ecological Applications (20) 263-277
Hybridization and introgression between introduced and native salmonids threaten the continued persistence of many inland cutthroat trout species. Environmental models have been developed to predict the spread of introgression, but few studies have assessed the role of propagule pressure. We used an extensive set of fish stocking records and geographic...
Response of benthic macroinvertebrate communities to highway construction in an Appalachian watershed
Lara B. Hedrick, S.A. Welsh, James T. Anderson, L.-S. Lin, Y. Chen, X. Wei
2010, Hydrobiologia (641) 115-131
Highway construction in mountainous areas can result in sedimentation of streams, negatively impacting stream habitat, water quality, and biotic communities. We assessed the impacts of construction of a segment of Corridor H, a four-lane highway, in the Lost River watershed, West Virginia, by monitoring benthic macroinvertebrate communities and water quality,...
Milankovitch-scale correlations between deeply buried microbial populations and biogenic ooze lithology
I.W. Aiello, B.A. Bekins
2010, Geology (38) 79-82
The recent discoveries of large, active populations of microbes in the subseafloor of the world's oceans supports the impact of the deep biosphere biota on global biogeochemical cycles and raises important questions concerning the functioning of these extreme environments for life. These investigations demonstrated that subseafloor microbes are unevenly distributed...
Landscape effects on diets of two canids in Northwestern Texas: A multinomial modeling approach
P.R. Lemons, J.S. Sedinger, M.P. Herzog, P. S. Gipson, R.L. Gilliland
2010, Journal of Mammalogy (91) 66-78
Analyses of feces, stomach contents, and regurgitated pellets are common techniques for assessing diets of vertebrates and typically contain more than 1 food item per sampling unit. When analyzed, these individual food items have traditionally been treated as independent, which represents pseudoreplication. When food types are recorded as present or...
Population synchrony of a native fish across three Laurentian Great Lakes: Evaluating the effects of dispersal and climate
D.B. Bunnell, J.V. Adams, O. T. Gorman, C.P. Madenjian, S.C. Riley, E.F. Roseman, J.S. Schaeffer
2010, Oecologia (162) 641-651
Climate and dispersal are the two most commonly cited mechanisms to explain spatial synchrony among time series of animal populations, and climate is typically most important for fishes. Using data from 1978-2006, we quantified the spatial synchrony in recruitment and population catch-per-unit-effort (CPUE) for bloater (Coregonus hoyi) populations across lakes...
Probable causes of increasing brucellosis in free-ranging elk of the Greater Yellowstone Ecosystem
Paul C. Cross, E.K. Cole, A. P. Dobson, W.H. Edwards, K.L. Hamlin, G. Luikart, A.D. Middleton, B.M. Scurlock, P.J. White
2010, Ecological Applications (20) 278-288
While many wildlife species are threatened, some populations have recovered from previous overexploitation, and data linking these population increases with disease dynamics are limited. We present data suggesting that free-ranging elk (Cervus elaphus) are a maintenance host for Brucella abortus in new areas of the Greater Yellowstone Ecosystem (GYE). Brucellosis...
Silica-rich deposits and hydrated minerals at Gusev Crater, Mars: Vis-NIR spectral characterization and regional mapping
M.S. Rice, J.F. Bell III, E.A. Cloutis, A. Wang, S. W. Ruff, M.A. Craig, D.T. Bailey, J. R. Johnson, P.A. De Souza Jr., W. H. Farrand
2010, Icarus (205) 375-395
The Mars Exploration Rover (MER) Spirit has discovered surprisingly high concentrations of amorphous silica in soil and nodular outcrops in the Inner Basin of the Columbia Hills. In Pancam multispectral observations, we find that an absorption feature at the longest Pancam wavelength (1009 nm) appears to be characteristic of these...
Long-term variability in Northern Hemisphere snow cover and associations with warmer winters
G.J. McCabe, D.M. Wolock
2010, Climatic Change (99) 141-153
A monthly snow accumulation and melt model is used with gridded monthly temperature and precipitation data for the Northern Hemisphere to generate time series of March snow-covered area (SCA) for the period 1905 through 2002. The time series of estimated SCA for March is verified by comparison with previously published...
Decadal-timescale estuarine geomorphic change under future scenarios of climate and sediment supply
N. K. Ganju, D. H. Schoellhamer
2010, Estuaries and Coasts (33) 15-29
Future estuarine geomorphic change, in response to climate change, sea-level rise, and watershed sediment supply, may govern ecological function, navigation, and water quality. We estimated geomorphic changes in Suisun Bay, CA, under four scenarios using a tidal-timescale hydrodynamic/sediment transport model. Computational expense and data needs were reduced using the morphological...
Exploring the limits of identifying sub-pixel thermal features using ASTER TIR data
R. Greg Vaughan, Laszlo P. Keszthelyi, Ashley G. Davies, David J. Schneider, Cheryl Jaworowski, Henry Heasler
2010, Journal of Volcanology and Geothermal Research (189) 225-237
Understanding the characteristics of volcanic thermal emissions and how they change with time is important for forecasting and monitoring volcanic activity and potential hazards. Satellite instruments view volcanic thermal features across the globe at various temporal and spatial resolutions. Thermal features that may be a precursor to a major eruption,...
Testing alternative models of climate-mediated extirpations
E.A. Beever, R.A.Y. Chris, P.W. Mote, J.L. Wilkening
2010, Ecological Applications (20) 164-178
Biotic responses to climate change will vary among taxa and across latitudes, elevational gradients, and degrees of insularity. However, due to factors such as phenotypic plasticity, ecotypic variation, and evolved tolerance to thermal stress, it remains poorly understood whether losses should be greatest in populations experiencing the greatest climatic change...
Patterns of Tamarix water use during a record drought
J.B. Nippert, J.J. Butler Jr., Gerard J. Kluitenberg, Donald O. Whittemore, D. Arnold, S.E. Spal, J.K. Ward
2010, Oecologia (162) 283-292
During a record drought (2006) in southwest Kansas, USA, we assessed groundwater dynamics in a shallow, unconfined aquifer, along with plant water sources and physiological responses of the invasive riparian shrub Tamarix ramosissima. In early May, diel water table fluctuations indicated evapotranspirative consumption of groundwater by vegetation. During the summer...
Evaluation of aquifer heterogeneity effects on river flow loss using a transition probability framework
N.B. Engdahl, E. T. Vogler, G.S. Weissmann
2010, Water Resources Research (46)
River-aquifer exchange is considered within a transition probability framework along the Rio Grande in Albuquerque, New Mexico, to provide a stochastic estimate of aquifer heterogeneity and river loss. Six plausible hydrofacies configurations were determined using categorized drill core and wetland survey data processed through the TPROGS geostatistical package. A base...
Model selection bias and Freedman's paradox
P.M. Lukacs, K.P. Burnham, David R. Anderson
2010, Annals of the Institute of Statistical Mathematics (62) 117-125
In situations where limited knowledge of a system exists and the ratio of data points to variables is small, variable selection methods can often be misleading. Freedman (Am Stat 37:152-155, 1983) demonstrated how common it is to select completely unrelated variables as highly "significant" when the number of data points...
In situ measurements of volatile aromatic hydrocarbon biodegradation rates in groundwater
I.M. Cozzarelli, B.A. Bekins, R.P. Eganhouse, E. Warren, H.I. Essaid
2010, Journal of Contaminant Hydrology (111) 48-64
Benzene and alkylbenzene biodegradation rates and patterns were measured using an in situ microcosm in a crude-oil contaminated aquifer near Bemidji, Minnesota. Benzene-D6, toluene, ethylbenzene, o-, m- and p-xylenes and four pairs of C3- and C4-benzenes were added to an in situ microcosm and studied over a 3-year period. The...
Morphologic dating of fault scarps using airborne laser swath mapping (ALSM) data
G.E. Hilley, S. Delong, C. Prentice, K. Blisniuk, J.R. Arrowsmith Jr.
2010, Geophysical Research Letters (37)
Models of fault scarp morphology have been previously used to infer the relative age of different fault scarps in a fault zone using labor-intensive ground surveying. We present a method for automatically extracting scarp morphologic ages within high-resolution digital topography. Scarp degradation is modeled as a diffusive mass transport process...
On the specification of structural equation models for ecological systems
James B. Grace, T. Michael Anderson, Han Olff, S.M. Scheiner
2010, Ecological Monographs (80) 67-87
The use of structural equation modeling (SEM) is often motivated by its utility for investigating complex networks of relationships, but also because of its promise as a means of representing theoretical concepts using latent variables. In this paper, we discuss characteristics of ecological theory and some of the challenges for...