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A Gibbs sampler for Bayesian analysis of site-occupancy data
Robert M. Dorazio, Daniel Taylor Rodriguez
2012, Methods in Ecology and Evolution (3) 1093-1098
1. A Bayesian analysis of site-occupancy data containing covariates of species occurrence and species detection probabilities is usually completed using Markov chain Monte Carlo methods in conjunction with software programs that can implement those methods for any statistical model, not just site-occupancy models. Although these software programs are quite flexible, considerable...
A terrestrial lidar-based workflow for determining three-dimensional slip vectors and associated uncertainties
Peter O. Gold, Eric Cowgill, Oliver Kreylos, Ryan D. Gold
2012, Geosphere (8) 431-442
Three-dimensional (3D) slip vectors recorded by displaced landforms are difficult to constrain across complex fault zones, and the uncertainties associated with such measurements become increasingly challenging to assess as landforms degrade over time. We approach this problem from a remote sensing perspective by using terrestrial laser scanning (TLS) and 3D...
Short-term impacts of a 4-lane highway on black bears in eastern North Carolina
Frank T. van Manen, Matthew F. McCollister, Jeremy M. Nicholson, Laura M. Thompson, Jason L. Kindall, Mark D. Jones
2012, Wildlife Monographs (181) 1-35
Among numerous anthropogenic impacts on terrestrial landscapes, expanding transportation networks represent one of the primary challenges to wildlife conservation worldwide. Larger mammals may be particularly vulnerable because of typically low densities, low reproductive rates, and extensive movements. Although numerous studies have been conducted to document impacts of road networks on...
A graphical method to evaluate predominant geochemical processes occurring in groundwater systems for radiocarbon dating
Liang-Feng Han, Niel Plummer, Pradeep Aggarwal
2012, Chemical Geology (318-319) 88-112
A graphical method is described for identifying geochemical reactions needed in the interpretation of radiocarbon age in groundwater systems. Graphs are constructed by plotting the measured 14C, δ13C, and concentration of dissolved inorganic carbon and are interpreted according to specific criteria to recognize water samples that are consistent with a...
Kinetics of uncatalyzed thermochemical sulfate reduction by sulfur-free paraffin
Tongwei Zhang, Geoffrey S. Ellis, Qisheng Ma, Alon Amrani, Yongchun Tang
2012, Geochimica et Cosmochimica Acta (96) 1-17
To determine kinetic parameters of sulfate reduction by hydrocarbons (HC) without the initial presence of low valence sulfur, we carried out a series of isothermal gold-tube hydrous-pyrolysis experiments at 320, 340, and 360 °C under a constant confined pressure of 24.1 MPa. The reactants used consisted of saturated HC (sulfur-free)...
ShakeMap Atlas 2.0: an improved suite of recent historical earthquake ShakeMaps for global hazard analyses and loss model calibration
D. Garcia, R.T. Mah, K. L. Johnson, M.G. Hearne, K. D. Marano, K.-W. Lin, D.J. Wald
2012, Conference Paper, The 15th World Conference on Earthquake Engineering: September 24-28, 2012, Lisbon, Portugal
We introduce the second version of the U.S. Geological Survey ShakeMap Atlas, which is an openly-available compilation of nearly 8,000 ShakeMaps of the most significant global earthquakes between 1973 and 2011. This revision of the Atlas includes: (1) a new version of the ShakeMap software that improves data usage and...
Estimating aboveground biomass in interior Alaska with Landsat data and field measurements
Lei Ji, Bruce K. Wylie, Dana R. Nossov, Birgit E. Peterson, Mark P. Waldrop, Jack W. McFarland, Jennifer R. Rover, Teresa N. Hollingsworth
2012, International Journal of Applied Earth Observation and Geoinformation (18) 451-461
Terrestrial plant biomass is a key biophysical parameter required for understanding ecological systems in Alaska. An accurate estimation of biomass at a regional scale provides an important data input for ecological modeling in this region. In this study, we created an aboveground biomass (AGB) map at 30-m resolution for the...
Abiotic and biotic controls of cryptobenthic fish assemblages across a Caribbean seascape
A.R. Harborne, H.L. Jelks, W. F. Smith-Vaniz, L.A. Rocha
2012, Coral Reefs (31) 977-990
The majority of fish studies on coral reefs consider only non-cryptic species and, despite their functional importance, data on cryptic species are scarce. This study investigates inter-habitat variation in Caribbean cryptobenthic fishes by re-analysing a comprehensive data set from 58 rotenone stations around Buck Island, U.S. Virgin Islands. Boosted regression...
Calibration and intercomparison of acetic acid measurements using proton transfer reaction mass spectrometry (PTR-MS)
K.B. Haase, W.C. Keene, A.A.P. Pszenny, H.R. Mayne, R.W. Talbot, B.C. Sive
2012, Atmospheric Measurement Techniques (5) 4635-4665
Acetic acid is one of the most abundant organic acids in the ambient atmosphere, with maximum mixing ratios reaching into the tens of parts per billion by volume (ppbv) range. The identities and associated magnitudes of the major sources and sinks for acetic acid are poorly characterized, due in part...
An evaluation of a mitigation strategy for deer-vehicle collisions
John A. Bissonette, Silvia Rosa
2012, Wildlife Biology (18) 414-423
High mule deer Odocoileus hemionus mortality in southwestern Utah led to the establishment of a mitigation strategy with two major objectives: 1) reduction of wildlife-vehicle collisions and 2) restoration of landscape connectivity to facilitate wildlife movement across the roaded landscape. During our study, we assessed the effectiveness of the mitigation...
Estimating and predicting collection probability of fish at dams using multistate modeling
John M. Plumb, William P. Connor, Kenneth F. Tiffan, Christine M. Moffitt, Russell W. Perry, Noah S. Adams
2012, Transactions of the American Fisheries Society (141) 1364-1373
Dams can be equipped with a bypass that routes a portion of the fish that enter the turbine intakes away from the powerhouse into flumes, where they can be counted. Daily passage abundance can be estimated by dividing the number of fish counted in the bypass by the sampling rate and then...
Factors influencing geographic patterns in diversity of forest bird communities of eastern Connecticut, USA
Robert J. Craig, Robert W. Klaver
2012, Ecography (36) 599-609
At regional scales, the most important variables associated with diversity are latitudinally-based temperature and net primary productivity, although diversity is also influenced by habitat. We examined bird species richness, community density and community evenness in forests of eastern Connecticut to determine whether: 1) spatial and seasonal patterns exist in diversity,...
Occupancy rates of primary burrowing crayfish in natural and disturbed large river bottomlands
Zachary J. Loughman, Stuart A. Welsh, Thomas P. Simon
2012, Journal of Crustacean Biology (32) 557-564
Among crayfish, primary burrowing species are the least understood ecologically. Many primary burrowing crayfish inhabit floodplains where forested landscapes have been fragmented by agricultural, industrial, or residential uses. In this study, site occupancy rates (ψ) were modeled for two primary burrowing crayfish, Fallicambarus fodiens (Cottle, 1863) and Cambarus thomai Jezerinac,...
High-frequency remote monitoring of large lakes with MODIS 500 m imagery
Ian M. McCullough, Cynthia S. Loftin, Steven A. Sader
2012, Remote Sensing of Environment (124) 234-241
Satellite-based remote monitoring programs of regional lake water quality largely have relied on Landsat Thematic Mapper (TM) owing to its long image archive, moderate spatial resolution (30 m), and wide sensitivity in the visible portion of the electromagnetic spectrum, despite some notable limitations such as temporal resolution (i.e., 16 days), data pre-processing...
Strategies to control a common carp population by pulsed commercial harvest
Michael E. Colvin, Clay Pierce, Timothy W. Stewart, Scott E. Grummer
2012, North American Journal of Fisheries Management (32) 1251-1264
Commercial fisheries are commonly used to manage nuisance fishes in freshwater systems, but such efforts are often unsuccessful. Strategies for successfully controlling a nuisance population of common carp Cyprinus carpio by pulsed commercial harvest were evaluated with a combination of (1) field sampling, (2) population estimation and CPUE indexing, and (3) simulation...
Interactive terrain visualization enables virtual field work during rapid scientific response to the 2010 Haiti earthquake
Eric Cowgill, Tony S. Bernardin, Michael E. Oskin, Christopher Bowles, M. Burak Yikilmaz, Oliver Kreylos, Austin J. Elliott, Scott Bishop, Ryan D. Gold, Alexander Morelan, Gerald W. Bawden, Bernd Hamann, Louise Kellogg
2012, Geosphere (8) 787-804
The moment magnitude (Mw) 7.0 12 January 2010 Haiti earthquake is the first major earthquake for which a large-footprint LiDAR (light detection and ranging) survey was acquired within several weeks of the event. Here, we describe the use of virtual reality data visualization to analyze massive amounts (67 GB on...
Monitoring subsurface hydrologic response for precipitation-induced shallow landsliding in the San Francisco Bay area, California, USA
Brian D. Collins, Jonathan D. Stock, Lisa C. Weber, K. Whitman, N. Knepprath
2012, Conference Paper, Landslides and engineered slopes: Protecting society through improved understanding, Proceedings of the 11th International Symposium on Landslides
Intense winter storms in the San Francisco Bay area (SFBA) of California, USA often trigger shallow landslides. Some of these landslides mobilize into potentially hazardous debris flows. A growing body of research indicates that rainfall intensity-duration thresholds are insufficient for accurate prediction of landslide occurrence. In response, we have begun...
Post-fire land treatments and wind erosion -- lessons from the Milford Flat Fire, UT, USA
Mark E. Miller, Matthew A. Bowker, Richard L. Reynolds, Harland L. Goldstein
2012, Aeolian Research (7) 29-44
We monitored sediment flux at 25 plots located at the northern end of the 2007 Milford Flat Fire (Lake Bonneville Basin, west-central Utah) to examine the effectiveness of post-fire rehabilitation treatments in mitigating risks of wind erosion during the first 3 years post fire. Maximum values were recorded during Mar–Jul...
Using stable isotopes to test for trophic niche partitioning: a case study with stream salamanders and fish
Adam J. Sepulveda, Winsor H. Lowe, Peter P. Marra
2012, Freshwater Biology (57) 1399-1409
1. Stream salamanders and fish often co-occur even though fish prey on and outcompete salamanders. However, the mechanisms that allow palatable salamanders to coexist with fish are unknown. 2. We tested mechanisms in the field that promote coexistence between Idaho giant salamanders (Dicamptodon aterrimus) and stream salmonid fishes in headwater streams. Previous research...
Automated measurement of diatom size
Sarah A. Spaulding, David H. Jewson, Rebecca J. Bixby, Harry Nelson, Diane M. McKnight
2012, Limnology and Oceanography: Methods (10) 882-890
Size analysis of diatom populations has not been widely considered, but it is a potentially powerful tool for understanding diatom life histories, population dynamics, and phylogenetic relationships. However, measuring cell dimensions on a light microscope is a time-consuming process. An alternative technique has been developed using digital flow cytometry on...
Structural equation modeling and the analysis of long-term monitoring data
James B. Grace, Jon E. Keeley, Darren Johnson, A Kenneth Bollen Kenneth
2012, Book chapter, Design and analysis of long-term ecological monitoring studies
The analysis of long-term monitoring data is increasingly important; not only for the discovery and documentation of changes in environmental systems, but also as an enterprise whose fruits validate the allocation of effort and scarce funds to monitoring. In simple terms, we may distinguish between the detection of change in...
Extended Kalman Filter framework for forecasting shoreline evolution
Joseph Long, Nathaniel G. Plant
2012, Geophysical Research Letters (39)
A shoreline change model incorporating both long- and short-term evolution is integrated into a data assimilation framework that uses sparse observations to generate an updated forecast of shoreline position and to estimate unobserved geophysical variables and model parameters. Application of the assimilation algorithm provides quantitative statistical estimates of combined model-data...
Helicopter electromagnetic data map ice thickness at Mount Adams and Mount Baker, Washington, USA
Carol A. Finn, Maria Deszcz-Pan, Paul A. Bedrosian
2012, Journal of Glaciology (58) 1133-1143
Ice-thickness measurements critical for flood and mudflow hazard studies are very sparse on Cascade Range (North America) volcanoes. Helicopter electromagnetic (HEM) data collected to detect hydrothermal alteration are used to determine ice thickness over portions of Mount Baker and Mount Adams volcanoes. A laterally continuous inversion method provides good estimates...
Genetic variation reveals influence of landscape connectivity on population dynamics and resiliency of western trout in disturbance-prone habitats
Helen M. Neville, Robert E. Gresswell, Jason B. Dunham
2012, Technical Report RMRS-GTR-290
Salmonid fishes have evolved and persisted in dynamic ecosystems where disturbance events vary in frequency, magnitude, timing, and duration, as well as the specific nature of associated effects (e.g., changes in thermal or flow regimes, geomorphology, or water chemistry). In the western United States, one of the major drivers of...
Status and trends of prey fish populations in Lake Michigan, 2012
David B. Bunnell, Charles P. Madenjian, Timothy J. Desorcie, Melissa Jean Kostich, Kelley Smith, Jean V. Adams
2012, Report
The U.S. Geological Survey Great Lakes Science Center has conducted lake-wide surveys of the fish community in Lake Michigan each fall since 1973 using standard 12-m bottom trawls towed along contour at depths of 9 to 110 m at each of seven index transects. The resulting data on relative abundance,...